CVE-2026-43620

MEDIUMNVD 5.56.5▲
EchelonGraph scoreMEDIUM confidence

Score 6.5 from GitHub Security Advisory published 2026-05-20. NVD baseline CVSS 5.5; sources differ by 1.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
6.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.5Exploit: None knownExposed: 0

A fix is available — apply it.

Rsync version 3.4.2 and prior contain a receiver-side out-of-bounds array read vulnerability in recv_files() in receiver.c that allows a malicious rsync server to crash the rsync client process. Attackers can exploit the vulnerability by setting CF_INC_RECURSE in compatibility flags and sending a specially crafted file list where the first sorted entry is not the leading dot directory, followed by a transfer record with ndx=0 and an iflag word without ITEM_TRANSFER, causing the receiver to read 8 bytes before the allocated pointer array and dereference an invalid pointer at an unmapped address, resulting in a deterministic SIGSEGV crash of the rsync client.

CVSS v3
5.5
EG Score
6.5(medium)
EG Risk
29(Track)
EG Risk 29/100SSVC: Track

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
Severity65% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
36%
KEV
Not listed

Published

May 20, 2026

Last Modified

July 24, 2026

Advisory Details (3)

Auto-updated May 20, 2026
Patch available. Sources: github.
generic

Rsync < 3.4.3 Out-of-Bounds Array Read via recv_files() | Advisories | VulnCheck

https://www.vulncheck.com/advisories/rsync-out-of-bounds-array-read-via-recv-files
github Patch Available

rsync: receiver-side out-of-bounds read enables remote DoS from malicious server · Advisory · RsyncProject/rsync · GitHub

https://github.com/RsyncProject/rsync/security/advisories/GHSA-28pw-r563-rxvm
generic

Release v3.4.3 · RsyncProject/rsync · GitHub

https://github.com/RsyncProject/rsync/releases/tag/v3.4.3

Vendor Advisories for CVE-2026-43620(2)

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

Patch Availability(2)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntursync (3.1.0-2ubuntu0.4+esm3) @ trusty2026-08-23ubuntu
ubuntursync (3.4.1+ds1-7ubuntu0.2) @ resolute2026-08-23ubuntu

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

(9 across 9 ecosystems)
Alpine:v3.20(1)
PackageVulnerable rangeFixed inDependents
rsync—3.4.3-r0—
Alpine:v3.21(1)
PackageVulnerable rangeFixed inDependents
rsync—3.4.3-r0—
Alpine:v3.22(1)
PackageVulnerable rangeFixed inDependents
rsync—3.4.3-r0—
Alpine:v3.23(1)
PackageVulnerable rangeFixed inDependents
rsync—3.4.3-r0—
Alpine:v3.24(1)
PackageVulnerable rangeFixed inDependents
rsync—3.4.3-r0—
Debian:11(1)
PackageVulnerable rangeFixed inDependents
rsync3.2.3-4, 3.2.3-4+deb11u1, 3.2.3-4+deb11u2, 3.2.3-4+deb11u33.2.3-4+deb11u4—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
rsync3.2.7-1, 3.2.7-1+deb12u1, 3.2.7-1+deb12u2, 3.2.7-1+deb12u3, 3.2.7-1+deb12u43.2.7-1+deb12u5—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
rsync3.4.1+ds1-5, 3.4.1+ds1-5+deb13u1, 3.4.1+ds1-5+deb13u23.4.1+ds1-5+deb13u3—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
rsync3.4.1+ds1-5 ... 3.4.2+ds1-2 (6 versions)3.4.3+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 5× in last 7d / 66× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. 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. Most recent first.

Showing the most recent 100 of 221 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-43620?
CVE-2026-43620 is a medium vulnerability published on May 20, 2026. Rsync version 3.4.2 and prior contain a receiver-side out-of-bounds array read vulnerability in recvfiles() in receiver.c that allows a malicious rsync server to crash the rsync client process. Attackers can exploit the vulnerability by setting CFINCRECURSE in compatibility flags and sending a…
When was CVE-2026-43620 disclosed?
CVE-2026-43620 was first published in the National Vulnerability Database on May 20, 2026, with the most recent update on July 24, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-43620 actively exploited?
CVE-2026-43620 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 64.2% of all scored CVEs.
What is the CVSS score of CVE-2026-43620?
CVE-2026-43620 has a CVSS v3 base score of 5.5 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 6.5.
How do I remediate CVE-2026-43620?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-43620, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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