CVE-2026-53791

CRITICALPre-NVD 9.19.1
EchelonGraph scoreMEDIUM confidence

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

This critical-severity CVE scores 9.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.5% (41st percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.

Triggered by: Headline CVSS from a secondary CVSS source
Sources: EPSS, a secondary CVSS source
Trending — Patch released this week
9.1EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.5%CVSS: 9.1Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

rsync daemon before 3.5.0 contains an IP address spoofing vulnerability that allows unauthenticated remote attackers to bypass IP-based access controls by sending a crafted PROXY protocol header with a forged source address. Attackers who can connect directly to the rsync daemon can inject a spoofed source IP in the PROXY protocol header to circumvent hosts allow/deny rules, gaining unauthorized access that would otherwise be blocked based on their real source address.

CVSS v3
9.1
EG Score
9.1CRITICALmedium confidence
EG Risk
41
EG Risk 41/100

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed (value × EchelonGraph’s weight)
Severity91% × 45%
The EG Score, 9.1 of 10.
Exploitation0.5% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at every mission impact level.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (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.
EPSS PROB
0.5%
EPSS %ILE
41st
KEV
Not listed

SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.

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

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (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)60 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 Vulnrichment) · Technical impact partial (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

August 13, 2026

Last Modified

August 31, 2026

Advisory Details (3)

Auto-updated Sep 15, 2026
Patch available. Sources: github_release, github.
Web page

rsync < 3.5.0 Daemon IP Spoofing via PROXY Protocol Header | Advisories | VulnCheck

https://www.vulncheck.com/advisories/rsync-daemon-ip-spoofing-via-proxy-protocol-header
GitHub advisoryMentions a patch (unverified)

rsync: PROXY-protocol mode lets a direct client spoof the daemon's source address · Advisory · RsyncProject/rsync · GitHub

Affected: 3.5.0. (Precise introduced-in ranges being finalised.)

https://github.com/RsyncProject/rsync/security/advisories/GHSA-h2q9-5fr8-w635
GitHub release Patch Available

v3.5.0

Patch available: RsyncProject/rsync v3.5.0

https://github.com/RsyncProject/rsync/releases/tag/v3.5.0

Vendor Advisories for CVE-2026-53791(3)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(4)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatcostmanagement/costmanagement-ui-rhel10:17914608512026-10-08redhat
redhatopenshift/ose-rhel-coreos-9:4.22.9.8.202609221802-02026-09-29redhat
redhatrsync-0:3.5.0-3.el10_22026-09-14redhat
redhatrsync-0:3.2.7-1.el9_82026-09-14redhat

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

(7 across 7 ecosystems)
Alpine:v3.21(1)
PackageVulnerable rangeFix by version rangeDependents
rsync—
  • every version up to 3.5.0-r0: fixed in 3.5.0-r0
—
Alpine:v3.22(1)
PackageVulnerable rangeFix by version rangeDependents
rsync—
  • every version up to 3.5.0-r0: fixed in 3.5.0-r0
—
Alpine:v3.23(1)
PackageVulnerable rangeFix by version rangeDependents
rsync—
  • every version up to 3.5.0-r0: fixed in 3.5.0-r0
—
Alpine:v3.24(1)
PackageVulnerable rangeFix by version rangeDependents
rsync—
  • every version up to 3.5.0-r0: fixed in 3.5.0-r0
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
rsync3.2.7-1 ... 3.5.1+ds1-1 (32 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
rsync3.4.1+ds1-5 ... 3.4.4+ds1-1 (13 versions)
  • every version up to 3.5.0+ds1-0+deb13u1: fixed in 3.5.0+ds1-0+deb13u1
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
rsync3.4.1+ds1-5 ... 3.4.4+ds1-1 (9 versions)
  • every version up to 3.5.0+ds1-1: fixed in 3.5.0+ds1-1
—

Weakness Classification(1)

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 16× in last 7d / 134× 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 100 of 196 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. None are among the latest 100 rows. The 96 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-14 01:59 UTCEG score recompute
  2. 2026-10-14 01:59 UTCVendor advisory
  3. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  4. 2026-10-12 22:16 UTCEG score recompute
  5. 2026-10-12 22:16 UTCVendor advisory
  6. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  7. 2026-10-12 15:57 UTCEG score recompute
  8. 2026-10-12 07:00 UTCVendor advisory
  9. 2026-10-11 19:40 UTCEG score recompute
  10. 2026-10-11 16:55 UTCEG score recompute
  11. 2026-10-11 14:18 UTCEG score recompute
  12. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  13. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  14. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  15. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  16. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  17. 2026-10-07 07:39 UTCVendor advisory
  18. 2026-10-07 03:06 UTCVendor advisory
  19. 2026-10-06 23:00 UTCVendor advisory
  20. 2026-10-06 17:30 UTCEG score recompute
  21. 2026-10-06 17:30 UTCVendor advisory
  22. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  23. 2026-10-06 13:25 UTCVendor advisory
  24. 2026-10-05 18:58 UTCEG score recompute
  25. 2026-10-05 18:58 UTCVendor advisory
Show 75 more
  1. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  2. 2026-10-05 14:38 UTCVendor advisory
  3. 2026-10-05 06:56 UTCVendor advisory
  4. 2026-10-05 02:32 UTCEG score recompute
  5. 2026-10-05 02:32 UTCVendor advisory
  6. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  7. 2026-10-04 22:21 UTCVendor advisory
  8. 2026-10-04 16:36 UTCVendor advisory
  9. 2026-10-04 12:18 UTCVendor advisory
  10. 2026-10-04 08:12 UTCVendor advisory
  11. 2026-10-04 03:50 UTCVendor advisory
  12. 2026-10-03 19:49 UTCEG score recompute
  13. 2026-10-03 19:49 UTCVendor advisory
  14. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  15. 2026-10-03 01:57 UTCVendor advisory
  16. 2026-10-02 21:52 UTCEG score recompute
  17. 2026-10-02 21:52 UTCVendor advisory
  18. 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  19. 2026-10-02 16:08 UTCVendor advisory
  20. 2026-10-02 07:34 UTCEG score recompute
  21. 2026-10-02 07:34 UTCVendor advisory
  22. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  23. 2026-10-01 14:26 UTCVendor advisory
  24. 2026-10-01 10:21 UTCVendor advisory
  25. 2026-10-01 06:17 UTCVendor advisory
  26. 2026-10-01 02:12 UTCVendor advisory
  27. 2026-09-30 21:47 UTCEG score recompute
  28. 2026-09-30 21:47 UTCVendor advisory
  29. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  30. 2026-09-29 15:22 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  31. 2026-09-29 08:19 UTCVendor advisory
  32. 2026-09-29 04:05 UTCEG score recompute
  33. 2026-09-29 04:05 UTCVendor advisory
  34. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  35. 2026-09-28 13:09 UTCVendor advisory
  36. 2026-09-28 09:01 UTCVendor advisory
  37. 2026-09-28 04:56 UTCVendor advisory
  38. 2026-09-28 00:48 UTCVendor advisory
  39. 2026-09-27 16:51 UTCEG score recompute
  40. 2026-09-27 16:51 UTCVendor advisory
  41. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  42. 2026-09-27 09:45 UTCEG score recompute
  43. 2026-09-27 09:45 UTCVendor advisory
  44. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  45. 2026-09-25 11:58 UTCVendor advisory
  46. 2026-09-25 07:39 UTCVendor advisory
  47. 2026-09-25 03:34 UTCEG score recompute
  48. 2026-09-25 03:34 UTCVendor advisory
  49. 2026-09-24 14:04 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  50. 2026-09-24 13:10 UTCVendor advisory
  51. 2026-09-24 09:05 UTCVendor advisory
  52. 2026-09-24 05:00 UTCVendor advisory
  53. 2026-09-24 00:55 UTCVendor advisory
  54. 2026-09-23 20:50 UTCEG score recompute
  55. 2026-09-23 20:50 UTCVendor advisory
  56. 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  57. 2026-09-23 13:31 UTCVendor advisory
  58. 2026-09-23 09:17 UTCVendor advisory
  59. 2026-09-23 05:12 UTCVendor advisory
  60. 2026-09-23 01:06 UTCVendor advisory
  61. 2026-09-22 21:01 UTCEG score recompute
  62. 2026-09-22 21:01 UTCVendor advisory
  63. 2026-09-22 12:30 UTCVendor advisory
  64. 2026-09-22 08:25 UTCVendor advisory
  65. 2026-09-22 04:21 UTCVendor advisory
  66. 2026-09-22 00:16 UTCEG score recompute
  67. 2026-09-22 00:16 UTCVendor advisory
  68. 2026-09-21 19:56 UTCVendor advisory
  69. 2026-09-21 14:08 UTCVendor advisory
  70. 2026-09-21 09:32 UTCVendor advisory
  71. 2026-09-21 04:17 UTCVendor advisory
  72. 2026-09-21 00:09 UTCEG score recompute
  73. 2026-09-21 00:09 UTCVendor advisory
  74. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  75. 2026-09-20 20:02 UTCVendor advisory

Related CVEs(same product + same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-53791?
CVE-2026-53791 is a critical-severity vulnerability; its CVE record was published on August 13, 2026. rsync daemon before 3.5.0 contains an IP address spoofing vulnerability that allows unauthenticated remote attackers to bypass IP-based access controls by sending a crafted PROXY protocol header with a forged source address. Attackers who can connect directly to the rsync daemon can inject a…
When was CVE-2026-53791 made public?
CVE-2026-53791 was made public on August 12, 2026: that is the date its CVE record's CNA, VulnCheck, gives for when the vulnerability was made public. The CVE record itself was published on August 13, 2026. EchelonGraph's copy of the record carries a last-modified date of August 31, 2026; the record at its source may have been updated since.
Is CVE-2026-53791 actively exploited?
CVE-2026-53791 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.5% probability of exploitation in the next 30 days (41st percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-53791?
CVE-2026-53791 has a CVSS base score of 9.1 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-53791?
A fix for CVE-2026-53791 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-53791 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-2026-53791

Explore →

Is Your Infrastructure Affected by CVE-2026-53791?

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

Book a Demo →Browse All CVEs