CVE-2023-27533

HIGHNVD 8.88.8
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to NVD's CVSS score.

Score 8.8 from GitHub Security Advisory (severity: HIGH) published 2023-03-30. NVD baseline CVSS 8.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3
Trending — 4 sources updated this weekElevated
8.8EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
CISA-KEV: Not listedEPSS PROB: 2.2%CVSS: 8.8Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

A vulnerability in input validation exists in curl <8.0 during communication using the TELNET protocol may allow an attacker to pass on maliciously crafted user name and "telnet options" during server negotiation. The lack of proper input scrubbing allows an attacker to send content or perform option negotiation without the application's intent. This vulnerability could be exploited if an application allows user input, thereby enabling attackers to execute arbitrary code on the system.

CVSS v3
8.8
EG Score
8.8HIGHmedium confidence
EG Risk
71
EG Risk 71/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity88% × 45%
Impact severity (EG Severity): CVSS 8.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low, Track* at medium and Attend at high mission impact.
Exploitation public PoC (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
2.2%
EPSS %ILE
82nd
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (8.8): severity, escalated by confirmed exploitation. This CVE's 8.8 is its impact severity (EG Severity), not escalated.

EG Severity
8.8 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
2.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-21). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track* at medium mission impactTrack at low, Track* at medium and Attend at high mission impact.CISA BOD 26-04: 3 days if the affected system is publicly exposed; 60 days if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low, Track* at medium and Attend at high mission impact.

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation public PoC (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)3 days if the affected system is publicly exposed; 60 days if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

March 30, 2023

Last Modified

October 14, 2026

Advisory Details (5)

Auto-updated Aug 12, 2026
Patch available.
Web page

curl: Multiple Vulnerabilities (GLSA 202310-12) — Gentoo security

https://security.gentoo.org/glsa/202310-12
Web page

[SECURITY] Fedora 36 Update: curl-7.82.0-14.fc36 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/36NBD5YLJXXEDZLDGNFCERWRYJQ6LAQW/
Web pageMentions a patch (unverified)

[SECURITY] [DLA 3398-1] curl security update

https://lists.debian.org/debian-lts-announce/2023/04/msg00025.html

Patch Availability(5)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubuntucurl (7.85.0-1ubuntu0.5) @ kinetic2026-05-25ubuntu
ubuntucurl (7.47.0-1ubuntu2.19+esm8) @ xenial2026-05-25ubuntu
redhatcurl-0:7.76.1-26.el92023-11-07redhat
redhatjbcs-httpd24-curl2023-06-05redhat
redhatjbcs-httpd24-curl-0:8.0.1-1.el7jbcs2023-06-05redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(16 across 16 ecosystems)
Alpine:v3.14(1)
PackageVulnerable rangeFix by version rangeDependents
curl—
  • 7.0.0 up to 8.0.1-r0: fixed in 8.0.1-r0
—
Alpine:v3.15(1)
PackageVulnerable rangeFix by version rangeDependents
curl—
  • 7.0.0 up to 8.0.1-r0: fixed in 8.0.1-r0
—
Alpine:v3.16(1)
PackageVulnerable rangeFix by version rangeDependents
curl—
  • 7.0.0 up to 8.0.1-r0: fixed in 8.0.1-r0
—
Alpine:v3.17(1)
PackageVulnerable rangeFix by version rangeDependents
curl—
  • 7.0.0 up to 7.88.1-r1: fixed in 7.88.1-r1
—
Alpine:v3.18(1)
PackageVulnerable rangeFix by version rangeDependents
curl—
  • 7.0.0 up to 8.0.0-r0: fixed in 8.0.0-r0
—
Alpine:v3.19(1)
PackageVulnerable rangeFix by version rangeDependents
curl—
  • 7.0.0 up to 8.0.0-r0: fixed in 8.0.0-r0
—
Alpine:v3.20(1)
PackageVulnerable rangeFix by version rangeDependents
curl—
  • 7.0.0 up to 8.0.0-r0: fixed in 8.0.0-r0
—
Alpine:v3.21(1)
PackageVulnerable rangeFix by version rangeDependents
curl—
  • 7.0.0 up to 8.0.0-r0: fixed in 8.0.0-r0
—
Alpine:v3.22(1)
PackageVulnerable rangeFix by version rangeDependents
curl—
  • 7.0.0 up to 8.0.0-r0: fixed in 8.0.0-r0
—
Alpine:v3.23(1)
PackageVulnerable rangeFix by version rangeDependents
curl—
  • 7.0.0 up to 8.0.0-r0: fixed in 8.0.0-r0
—
Alpine:v3.24(1)
PackageVulnerable rangeFix by version rangeDependents
curl—
  • 7.0.0 up to 8.0.0-r0: fixed in 8.0.0-r0
—
Debian:10(1)
PackageVulnerable rangeFix by version rangeDependents
curl7.64.0-4 ... 7.64.0-4+deb10u5 (6 versions)
  • every version up to 7.64.0-4+deb10u6: fixed in 7.64.0-4+deb10u6
—
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
curl7.74.0-1.3 ... 7.74.0-1.3+deb11u7~bpo11+1 (9 versions)
  • every version up to 7.74.0-1.3+deb11u8: fixed in 7.74.0-1.3+deb11u8
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
curl—
  • every version up to 7.88.1-7: fixed in 7.88.1-7
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
curl—
  • every version up to 7.88.1-7: fixed in 7.88.1-7
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
curl—
  • every version up to 7.88.1-7: fixed in 7.88.1-7
—

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Additional Vendor Advisories

(3)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 11× in last 7d / 42× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 94 of 206 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. 6 repeat rows among the latest 100 are merged into the row they repeat. The 112 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-23 16:29 UTCEPSS rescoreEPSS 2.2% · 82nd percentile
  2. 2026-10-22 16:31 UTCEPSS rescoreEPSS 2.2% · 82nd percentile
  3. 2026-10-22 10:29 UTCEG score recompute
  4. 2026-10-22 10:29 UTCVendor advisory
  5. 2026-10-22 10:28 UTCGHSA enrichmentGHSA-xvw3-6q4f-2gcv · GitHub severity HIGH · GitHub CVSS 8.8
  6. 2026-10-21 16:29 UTCEPSS rescoreEPSS 2.2% · 82nd percentile
  7. 2026-10-20 16:29 UTCEPSS rescoreEPSS 2.2% · 81st percentile
  8. 2026-10-19 16:29 UTCEPSS rescoreEPSS 2.2% · 81st percentile
  9. 2026-10-18 16:29 UTCEPSS rescoreEPSS 2.2% · 81st percentile
  10. 2026-10-18 08:08 UTCEG score recompute
  11. 2026-10-17 16:29 UTCEPSS rescoreEPSS 2.2% · 81st percentile
  12. 2026-10-16 16:35 UTCEPSS rescoreEPSS 2.2% · 81st percentile
  13. 2026-10-15 16:29 UTCEPSS rescoreEPSS 2.2% · 81st percentile
  14. 2026-10-14 23:45 UTCVendor advisory
  15. 2026-10-14 23:44 UTCGHSA enrichmentGHSA-xvw3-6q4f-2gcv · GitHub severity HIGH · GitHub CVSS 8.8
  16. 2026-10-14 22:35 UTCEG score recompute
  17. 2026-10-14 22:35 UTCVendor advisory
  18. 2026-10-14 22:34 UTCGHSA enrichmentGHSA-xvw3-6q4f-2gcv · GitHub severity HIGH · GitHub CVSS 8.8
  19. 2026-10-14 16:29 UTCEPSS rescoreEPSS 2.0% · 80th percentile
  20. 2026-10-14 15:24 UTCOSV refresh
  21. 2026-10-13 16:29 UTCEPSS rescoreEPSS 2.0% · 80th percentile
  22. 2026-10-12 18:30 UTCEG score recompute
  23. 2026-10-12 16:30 UTCEPSS rescoreEPSS 2.0% · 80th percentile
  24. 2026-10-11 21:56 UTCEG score recompute
  25. 2026-10-11 13:45 UTCEPSS rescoreEPSS 2.0% · 80th percentile
Show 69 more
  1. 2026-10-10 19:57 UTCEPSS rescoreEPSS 2.0% · 80th percentile
  2. 2026-10-09 20:05 UTCEPSS rescoreEPSS 2.0% · 80th percentile
  3. 2026-10-08 17:06 UTCEPSS rescoreEPSS 2.0% · 80th percentile
  4. 2026-10-07 23:45 UTCEPSS rescoreEPSS 2.0% · 80th percentile
  5. 2026-10-06 15:15 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  6. 2026-10-05 17:41 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  7. 2026-10-04 23:20 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  8. 2026-10-03 14:23 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  9. 2026-10-02 16:23 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  10. 2026-10-01 19:47 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  11. 2026-09-30 16:20 UTCEG score recompute
  12. 2026-09-30 15:01 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  13. 2026-09-29 15:16 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  14. 2026-09-28 13:49 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  15. 2026-09-27 13:42 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  16. 2026-09-26 00:22 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  17. 2026-09-24 14:01 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  18. 2026-09-23 16:47 UTCOSV refresh
  19. 2026-09-23 13:45 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  20. 2026-09-22 14:45 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  21. 2026-09-16 14:05 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  22. 2026-09-12 14:58 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  23. 2026-09-11 14:50 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  24. 2026-09-11 09:34 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  25. 2026-09-08 21:57 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  26. 2026-09-07 15:59 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  27. 2026-09-06 13:45 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  28. 2026-09-05 15:25 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  29. 2026-09-04 13:58 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  30. 2026-09-04 11:29 UTCOSV refresh
  31. 2026-09-04 05:04 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  32. 2026-09-02 14:09 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  33. 2026-09-01 13:51 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  34. 2026-08-30 19:15 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  35. 2026-08-30 01:19 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  36. 2026-08-28 21:38 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  37. 2026-08-27 14:23 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  38. 2026-08-26 14:43 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  39. 2026-08-25 13:46 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  40. 2026-08-24 14:14 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  41. 2026-08-23 00:17 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  42. 2026-08-21 23:46 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  43. 2026-08-20 22:53 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  44. 2026-08-19 17:02 UTCEPSS rescoreEPSS 2.0% · 79th percentile
  45. 2026-08-18 13:46 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  46. 2026-08-17 21:59 UTCOSV refresh
  47. 2026-08-17 13:44 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  48. 2026-08-16 14:53 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  49. 2026-08-16 02:12 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  50. 2026-08-15 01:28 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  51. 2026-08-13 21:58 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  52. 2026-08-12 13:48 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  53. 2026-08-11 13:39 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  54. 2026-08-09 13:44 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  55. 2026-08-08 16:34 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  56. 2026-08-07 16:24 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  57. 2026-08-06 13:44 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  58. 2026-08-05 19:15 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  59. 2026-08-04 15:07 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  60. 2026-08-04 10:35 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  61. 2026-08-03 10:34 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  62. 2026-08-02 17:27 UTCOSV refresh
  63. 2026-08-02 02:24 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  64. 2026-08-01 04:13 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  65. 2026-07-30 16:26 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  66. 2026-07-30 01:28 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  67. 2026-07-28 15:34 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  68. 2026-07-27 14:10 UTCEPSS rescoreEPSS 2.0% · 78th percentile
  69. 2026-07-26 14:52 UTCEPSS rescoreEPSS 2.0% · 78th percentile

Frequently asked(5)

What is CVE-2023-27533?
CVE-2023-27533 is a high-severity vulnerability; its CVE record was published on March 30, 2023. A vulnerability in input validation exists in curl <8.0 during communication using the TELNET protocol may allow an attacker to pass on maliciously crafted user name and "telnet options" during server negotiation. The lack of proper input scrubbing allows an attacker to send content or perform…
When was the CVE record for CVE-2023-27533 published?
The CVE record for CVE-2023-27533 was published on March 30, 2023. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of October 14, 2026; the record at its source may have been updated since.
Is CVE-2023-27533 actively exploited?
CVE-2023-27533 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 2.2% probability of exploitation in the next 30 days (82nd percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2023-27533?
CVE-2023-27533 has a CVSS v3 base score of 8.8 (NVD).
How do I remediate CVE-2023-27533?
A fix for CVE-2023-27533 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2023-27533 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2023-27533

Explore →

Is Your Infrastructure Affected by CVE-2023-27533?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.