CVE-2023-49285

CRITICALNVD 7.59.0
EchelonGraph scoreHIGH confidence

“▲” beside the score: it is higher than NVD's CVSS score.

Score elevated to 9.0 because EPSS predicted 88% probability of exploitation within the next 30 days (99th percentile of EPSS-scored CVEs) when EchelonGraph scored this CVE. NVD baseline CVSS 7.5 retained for reference. Confidence: see factors.

Triggered by: EPSS exploit prediction (continuous uplift above 30%)
Sources: EPSS, NVD CVSS v3
Trending — 3 sources updated this weekElevated
9.0EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (the SSVC decision on this page).
  • High exploitation likelihood — EPSS 88%
CISA-KEV: Not listedEPSS PROB: 88%CVSS: 7.5Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Due to a Buffer Overread bug Squid is vulnerable to a Denial of Service attack against Squid HTTP Message processing. This bug is fixed by Squid version 6.5. Users are advised to upgrade. There are no known workarounds for this vulnerability.

CVSS v3
7.5
EG Score
9.0CRITICALhigh confidence
EG Risk
69
EG Risk 69/100

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)
Severity75% × 45%
Impact severity (EG Severity): CVSS 7.5 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation88% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's BOD 26-04 default: no one has published Automatable for this CVE, and CISA treats it as “no” for a CVE not in KEV.
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Track* at high (mission-essential systems).
Exploitation none (no CISA value, KEV listing or exploit code on record) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from 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.
EPSS PROB
88%
EPSS %ILE
99th
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 (9.0): severity, escalated by confirmed exploitation. This CVE's 9.0 is EPSS's lift toward 9.0 from its impact severity (EG Severity, CVSS 7.5 HIGH): a likelihood of exploitation, not impact.

EG Severity
7.5 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.NVD CVSS v3 · CVSS v3.0 or v3.1
EG Likelihood
88% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-22). 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 or medium mission impact; Track* at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade 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 or medium mission impact; Track* at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines.

Exploitation none (no CISA value, KEV listing or exploit code on record) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from 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)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). Where an input reads “CISA's BOD 26-04 default”, no one has published it for this CVE, and CISA's implementation guidance says: “If “Automatable” and “Technical Impact” information items about a CVE ID are not available and the CVE ID is not in the KEV Catalog, CISA will treat its values as “no” and “total,” respectively, until CISA or a third party provides metadata about the CVE ID. CISA will always provide the Vulnrichment data for a CVE ID listed in the KEV Catalog.” 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

December 4, 2023

Last Modified

June 17, 2026

Advisory Details (9)

Auto-updated Oct 12, 2026
Patch available. Sources: github, github_commit.
Web page

[SECURITY] Fedora 38 Update: squid-6.6-1.fc38 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/[email protected]/message/MEV66D3PAAY6K7TWDT3WZBLCPLASFJDC/
Web page

[SECURITY] Fedora 39 Update: squid-6.6-1.fc39 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/[email protected]/message/A5QASTMCUSUEW3UOMKHZJB3FTONWSRXS/
Web pageMentions a patch (unverified)

[SECURITY] [DLA 3709-1] squid security update

https://lists.debian.org/debian-lts-announce/2024/01/msg00003.html
GitHub advisoryMentions a patch (unverified)

SQUID-2023:7 Denial of Service in HTTP Message Processing · Advisory · squid-cache/squid · GitHub

https://github.com/squid-cache/squid/security/advisories/GHSA-8w9r-p88v-mmx9
GitHub commit

commit deee944f9a12 (squid-cache/squid)

Fix landed in squid-cache/squid commit deee944f9a12 — awaiting tagged release

https://github.com/squid-cache/squid/commit/deee944f9a12c9fd399ce52f3e2526bb573a9470
GitHub commit

commit 77b3fb4df0f1 (squid-cache/squid)

Fix landed in squid-cache/squid commit 77b3fb4df0f1 — awaiting tagged release

https://github.com/squid-cache/squid/commit/77b3fb4df0f126784d5fd4967c28ed40eb8d521b

Patch Availability(11)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubuntusquidclient (3.5.12-1ubuntu7.16+esm3) @ xenial2026-10-19ubuntu
ubuntusquidclient (6.1-2ubuntu1.2) @ mantic2026-10-19ubuntu
redhatsquid-7:3.5.20-17.el7_9.102024-04-11redhat
redhatsquid-7:5.2-1.el9_0.42024-03-05redhat
redhatsquid:4-8020020240122164331.4cda2c842024-02-12redhat
redhatsquid:4-8060020231222131040.ad008a3a2024-02-12redhat
redhatsquid:4-8040020240122165847.522a0ee42024-02-12redhat
redhatsquid:4-8080020231222130009.63b345852024-01-24redhat
redhatsquid-7:5.5-6.el9_3.52024-01-08redhat
redhatsquid-7:5.5-5.el9_2.32024-01-08redhat
redhatsquid:4-8090020231207155957.a75119d52024-01-03redhat

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

(11 across 11 ecosystems)
Alpine:v3.19(1)
PackageVulnerable rangeFix by version rangeDependents
squid—
  • every version up to 6.5-r0: fixed in 6.5-r0
—
Alpine:v3.20(1)
PackageVulnerable rangeFix by version rangeDependents
squid—
  • every version up to 6.5-r0: fixed in 6.5-r0
—
Alpine:v3.21(1)
PackageVulnerable rangeFix by version rangeDependents
squid—
  • every version up to 6.5-r0: fixed in 6.5-r0
—
Alpine:v3.22(1)
PackageVulnerable rangeFix by version rangeDependents
squid—
  • every version up to 6.5-r0: fixed in 6.5-r0
—
Alpine:v3.23(1)
PackageVulnerable rangeFix by version rangeDependents
squid—
  • every version up to 6.5-r0: fixed in 6.5-r0
—
Alpine:v3.24(1)
PackageVulnerable rangeFix by version rangeDependents
squid—
  • every version up to 6.5-r0: fixed in 6.5-r0
—
Debian:10(1)
PackageVulnerable rangeFix by version rangeDependents
squid4.6-1 ... 4.6-1+deb10u8 (9 versions)
  • every version up to 4.6-1+deb10u9: fixed in 4.6-1+deb10u9
—
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
squid4.13-10, 4.13-10+deb11u1, 4.13-10+deb11u2
  • every version up to 4.13-10+deb11u3: fixed in 4.13-10+deb11u3
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
squid5.7-2
  • every version up to 5.7-2+deb12u1: fixed in 5.7-2+deb12u1
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
squid—
  • every version up to 6.5-1: fixed in 6.5-1
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
squid—
  • every version up to 6.5-1: fixed in 6.5-1
—

Weakness Classification(2)

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

Additional Vendor Advisories

(2)

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 14× in last 7d / 29× 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 84 of 104 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. 16 repeat rows among the latest 100 are merged into the row they repeat. The 20 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-22 20:39 UTCEG score recompute
  2. 2026-10-22 20:39 UTCVendor advisory
  3. 2026-10-21 18:12 UTCEG score recompute
  4. 2026-10-21 18:12 UTCVendor advisory
  5. 2026-10-21 16:29 UTCEPSS rescoreEPSS 88% · 99th percentile
  6. 2026-10-20 15:47 UTCEG score recompute
  7. 2026-10-20 15:47 UTCVendor advisory
  8. 2026-10-19 16:29 UTCEPSS rescoreEPSS 88% · 99th percentile
  9. 2026-10-19 13:21 UTCEG score recompute
  10. 2026-10-19 13:21 UTCVendor advisory
  11. 2026-10-18 10:57 UTCVendor advisory
  12. 2026-10-18 07:45 UTCEG score recompute
  13. 2026-10-17 05:25 UTCEG score recompute
  14. 2026-10-17 05:25 UTCVendor advisory
  15. 2026-10-16 03:00 UTCEG score recompute
  16. 2026-10-16 03:00 UTCVendor advisory
  17. 2026-10-14 23:04 UTCEG score recompute
  18. 2026-10-14 23:04 UTCVendor advisory
  19. 2026-10-14 16:30 UTCEPSS rescoreEPSS 88% · 99th percentile
  20. 2026-10-13 18:46 UTCEG score recompute
  21. 2026-10-13 18:46 UTCVendor advisory
  22. 2026-10-12 16:19 UTCEG score recompute
  23. 2026-10-12 16:19 UTCVendor advisory
  24. 2026-10-11 21:41 UTCEG score recompute
  25. 2026-10-09 20:05 UTCEPSS rescoreEPSS 88% · 99th percentile
Show 59 more
  1. 2026-09-30 19:14 UTCOSV refresh
  2. 2026-09-30 16:34 UTCEG score recompute
  3. 2026-09-26 00:22 UTCEPSS rescoreEPSS 88% · 99th percentile
  4. 2026-09-24 14:01 UTCEPSS rescoreEPSS 88% · 99th percentile
  5. 2026-09-22 14:46 UTCEPSS rescoreEPSS 88% · 99th percentile
  6. 2026-09-21 20:31 UTCEPSS rescoreEPSS 88% · 99th percentile
  7. 2026-09-20 20:14 UTCEPSS rescoreEPSS 88% · 99th percentile
  8. 2026-09-17 19:25 UTCEPSS rescoreEPSS 88% · 99th percentile
  9. 2026-09-16 14:06 UTCEPSS rescoreEPSS 88% · 99th percentile
  10. 2026-09-15 03:08 UTCEPSS rescoreEPSS 88% · 99th percentile
  11. 2026-09-12 02:10 UTCOSV refresh
  12. 2026-09-11 09:34 UTCEPSS rescoreEPSS 88% · 99th percentile
  13. 2026-09-07 15:59 UTCEPSS rescoreEPSS 88% · 99th percentile
  14. 2026-09-06 13:45 UTCEPSS rescoreEPSS 88% · 99th percentile
  15. 2026-09-05 15:26 UTCEPSS rescoreEPSS 88% · 99th percentile
  16. 2026-09-04 05:04 UTCEPSS rescoreEPSS 89% · 99th percentile
  17. 2026-08-30 19:15 UTCEPSS rescoreEPSS 89% · 99th percentile
  18. 2026-08-28 21:39 UTCEPSS rescoreEPSS 89% · 99th percentile
  19. 2026-08-27 14:23 UTCEPSS rescoreEPSS 89% · 99th percentile
  20. 2026-08-26 14:44 UTCEPSS rescoreEPSS 89% · 99th percentile
  21. 2026-08-25 13:46 UTCEPSS rescoreEPSS 89% · 99th percentile
  22. 2026-08-24 14:14 UTCEPSS rescoreEPSS 89% · 99th percentile
  23. 2026-08-24 07:57 UTCOSV refresh
  24. 2026-08-21 23:47 UTCEPSS rescoreEPSS 89% · 99th percentile
  25. 2026-08-15 01:28 UTCEPSS rescoreEPSS 89% · 99th percentile
  26. 2026-08-12 13:49 UTCEPSS rescoreEPSS 89% · 99th percentile
  27. 2026-08-08 16:35 UTCEPSS rescoreEPSS 89% · 99th percentile
  28. 2026-08-08 04:19 UTCOSV refresh
  29. 2026-08-07 16:25 UTCEPSS rescoreEPSS 89% · 99th percentile
  30. 2026-07-30 01:28 UTCEPSS rescoreEPSS 89% · 99th percentile
  31. 2026-07-25 14:16 UTCEPSS rescoreEPSS 89% · 99th percentile
  32. 2026-07-24 14:16 UTCEPSS rescoreEPSS 89% · 99th percentile
  33. 2026-07-23 02:28 UTCEG score recompute
  34. 2026-07-22 21:20 UTCEG score recompute▲ 0.40
  35. 2026-07-22 21:20 UTCVendor advisory
  36. 2026-07-22 14:06 UTCEPSS rescoreEPSS 89% · 99th percentile
  37. 2026-07-21 15:23 UTCEPSS rescoreEPSS 89% · 99th percentile
  38. 2026-07-15 16:56 UTCEPSS rescoreEPSS 89% · 99th percentile
  39. 2026-07-15 02:19 UTCOSV refresh
  40. 2026-07-07 13:44 UTCEPSS rescoreEPSS 89% · 99th percentile
  41. 2026-07-01 15:05 UTCEPSS rescoreEPSS 89% · 99th percentile
  42. 2026-06-27 03:07 UTCEPSS rescoreEPSS 89% · 99th percentile
  43. 2026-06-27 03:07 UTCOSV refresh
  44. 2026-06-24 14:04 UTCEPSS rescoreEPSS 89% · 99th percentile
  45. 2026-06-24 06:32 UTCNVD updateCVSS v3 → 7.5
  46. 2026-06-23 21:31 UTCEPSS rescoreEPSS 89% · 99th percentile
  47. 2026-06-22 14:24 UTCEPSS rescoreEPSS 89% · 99th percentile
  48. 2026-06-15 17:47 UTCEPSS rescoreEPSS 89% · 99th percentile
  49. 2026-06-14 23:16 UTCEPSS rescoreEPSS 9.6% · 93rd percentile
  50. 2026-06-13 22:59 UTCEPSS rescoreEPSS 9.6% · 93rd percentile
  51. 2026-06-12 23:10 UTCEPSS rescoreEPSS 9.6% · 93rd percentile
  52. 2026-06-11 13:59 UTCEPSS rescoreEPSS 9.6% · 93rd percentile
  53. 2026-06-10 22:17 UTCEPSS rescoreEPSS 9.6% · 93rd percentile
  54. 2026-06-10 13:21 UTCEPSS rescoreEPSS 9.6% · 93rd percentile
  55. 2026-06-09 13:47 UTCOSV refresh
  56. 2026-06-08 14:16 UTCEPSS rescoreEPSS 9.6% · 93rd percentile
  57. 2026-06-07 15:23 UTCEPSS rescoreEPSS 9.6% · 93rd percentile
  58. 2026-06-06 13:46 UTCEPSS rescoreEPSS 9.6% · 93rd percentile
  59. 2026-06-05 22:46 UTCEPSS rescoreEPSS 9.6% · 93rd percentile

Frequently asked(5)

What is CVE-2023-49285?
CVE-2023-49285 is a critical-severity vulnerability; its CVE record was published on December 4, 2023. Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Due to a Buffer Overread bug Squid is vulnerable to a Denial of Service attack against Squid HTTP Message processing. This bug is fixed by Squid version 6.5. Users are advised to upgrade. There are no known workarounds for…
When was the CVE record for CVE-2023-49285 published?
The CVE record for CVE-2023-49285 was published on December 4, 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 June 17, 2026; the record at its source may have been updated since.
Is CVE-2023-49285 actively exploited?
CVE-2023-49285 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 88% probability of exploitation in the next 30 days (99th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2023-49285?
CVE-2023-49285 has a CVSS v3 base score of 7.5 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.0 (CRITICAL).
How do I remediate CVE-2023-49285?
A fix for CVE-2023-49285 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2023-49285 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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