CVE-2026-59919

MEDIUMPre-NVD 5.55.5—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.1%, top 96% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
5.5EG
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

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1.136.Final and 4.2.16.Final, Netty's HAProxy encoder ( HAProxyMessageEncoder ) writes AF_UNIX source and destination socket addresses into the HAProxy V1 text protocol without validating them for CRLF characters, so an attacker who controls an AF_UNIX address can inject  \r\n  sequences and split the single PROXY header into multiple lines. This is possible because the V1 protocol uses CRLF as its line terminator and, unlike IPv4/IPv6 addresses whose format checks implicitly reject CRLF, AF_UNIX addresses are only validated for length (up to 108 bytes), allowing a forged second PROXY header line that spoofs the client source/destination IP to a downstream server or load balancer. The issue is fixed in versions 4.1.136.Final and 4.2.16.Final.

CVSS v3
5.5
EG Score
5.5(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
Severity55% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
4%
KEV
Not listed

Published

July 22, 2026

Last Modified

August 6, 2026

Advisory Details (1)

Auto-updated Jul 29, 2026
🔬 Proof of concept available. Patch available. Sources: github.
github Patch Available🟡 PoC Available

HAProxy V1 Protocol CRLF Injection via AF_UNIX Address · Advisory · netty/netty · GitHub

https://github.com/netty/netty/security/advisories/GHSA-wh89-7897-x99h

Vendor Advisories for CVE-2026-59919(1)

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

Affected Packages

(5 across 5 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
netty1:4.1.48-10 ... 1:4.1.48-9 (16 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
netty1:4.1.48-10 ... 1:4.1.48-9 (12 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
netty1:4.1.48-10 ... 1:4.1.48-16 (8 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
netty1:4.1.48-10 ... 1:4.1.48-16 (7 versions)——
Maven(1)
PackageVulnerable rangeFixed inDependents
io.netty:netty-codec-haproxy4.0.29.Final ... 4.1.99.Final (179 versions)4.1.136.Final—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 9× in last 7d / 44× 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.

  1. 2026-09-15 03:11 UTCEPSS rescore
  2. 2026-09-14 16:44 UTCEG score recompute
  3. 2026-09-13 16:47 UTCEPSS rescore
  4. 2026-09-12 17:48 UTCEG score recompute
  5. 2026-09-11 19:28 UTCEG score recompute
  6. 2026-09-11 14:53 UTCEPSS rescore
  7. 2026-09-10 21:14 UTCEG score recompute
  8. 2026-09-10 09:35 UTCEPSS rescore
  9. 2026-09-09 09:11 UTCEG score recompute
  10. 2026-09-08 22:01 UTCEPSS rescore
  11. 2026-09-07 21:39 UTCEG score recompute
  12. 2026-09-07 16:01 UTCEPSS rescore
  13. 2026-09-06 17:28 UTCEG score recompute
  14. 2026-09-06 13:47 UTCEPSS rescore
  15. 2026-09-05 19:33 UTCEG score recompute
  16. 2026-09-04 13:39 UTCEG score recompute
  17. 2026-09-04 05:07 UTCEPSS rescore
  18. 2026-09-02 14:12 UTCEPSS rescore
  19. 2026-09-01 23:37 UTCEG score recompute
  20. 2026-09-01 13:54 UTCEPSS rescore
  21. 2026-09-01 04:40 UTCEPSS rescore
  22. 2026-08-30 22:35 UTCEG score recompute
  23. 2026-08-30 19:17 UTCEPSS rescore
  24. 2026-08-30 01:22 UTCEPSS rescore
  25. 2026-08-30 00:50 UTCEG score recompute
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  1. 2026-08-28 21:42 UTCEPSS rescore
  2. 2026-08-28 01:32 UTCEG score recompute
  3. 2026-08-27 14:25 UTCEPSS rescore
  4. 2026-08-27 03:28 UTCEG score recompute
  5. 2026-08-26 14:46 UTCEPSS rescore
  6. 2026-08-26 05:41 UTCEG score recompute
  7. 2026-08-25 13:49 UTCEPSS rescore
  8. 2026-08-25 07:20 UTCEG score recompute
  9. 2026-08-24 09:32 UTCEG score recompute
  10. 2026-08-23 11:45 UTCEG score recompute
  11. 2026-08-23 00:19 UTCEPSS rescore
  12. 2026-08-21 16:14 UTCEG score recompute
  13. 2026-08-20 22:55 UTCEPSS rescore
  14. 2026-08-19 20:42 UTCEG score recompute
  15. 2026-08-19 17:04 UTCEPSS rescore
  16. 2026-08-18 19:11 UTCEG score recompute
  17. 2026-08-18 13:48 UTCEPSS rescore
  18. 2026-08-17 20:26 UTCEG score recompute
  19. 2026-08-17 13:47 UTCEPSS rescore
  20. 2026-08-16 20:01 UTCEG score recompute
  21. 2026-08-16 14:56 UTCEPSS rescore
  22. 2026-08-16 02:14 UTCEPSS rescore
  23. 2026-08-15 22:15 UTCEG score recompute
  24. 2026-08-15 01:30 UTCEPSS rescore
  25. 2026-08-14 02:42 UTCEG score recompute
  26. 2026-08-13 22:00 UTCEPSS rescore
  27. 2026-08-13 04:56 UTCEG score recompute
  28. 2026-08-12 13:51 UTCEPSS rescore
  29. 2026-08-11 09:24 UTCEG score recompute
  30. 2026-08-11 00:00 UTCEPSS rescore
  31. 2026-08-09 13:52 UTCEG score recompute
  32. 2026-08-09 13:46 UTCEPSS rescore
  33. 2026-08-08 16:37 UTCEPSS rescore
  34. 2026-08-07 18:21 UTCEG score recompute
  35. 2026-08-06 20:35 UTCEG score recompute
  36. 2026-08-06 13:47 UTCEPSS rescore
  37. 2026-08-06 01:09 UTCEG score recompute
  38. 2026-08-05 19:17 UTCEPSS rescore
  39. 2026-08-05 03:23 UTCEG score recompute
  40. 2026-08-04 10:39 UTCEPSS rescore
  41. 2026-08-04 05:37 UTCEG score recompute
  42. 2026-08-03 10:36 UTCEPSS rescore
  43. 2026-08-01 12:20 UTCEG score recompute
  44. 2026-08-01 04:16 UTCEPSS rescore
  45. 2026-07-30 16:47 UTCEG score recompute
  46. 2026-07-30 16:28 UTCEPSS rescore
  47. 2026-07-29 18:31 UTCEG score recompute
  48. 2026-07-27 07:34 UTCEG score recompute
  49. 2026-07-23 03:21 UTCEG score recompute
  50. 2026-07-22 22:26 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-59919?
CVE-2026-59919 is a medium vulnerability published on July 22, 2026. Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1.136.Final and 4.2.16.Final, Netty's HAProxy encoder ( HAProxyMessageEncoder ) writes AFUNIX source and destination socket addresses into the HAProxy V1 text protocol without validating them for CRLF…
When was CVE-2026-59919 disclosed?
CVE-2026-59919 was first published in the National Vulnerability Database on July 22, 2026, with the most recent update on August 6, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-59919 actively exploited?
CVE-2026-59919 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 96.4% of all scored CVEs.
What is the CVSS score of CVE-2026-59919?
CVE-2026-59919 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-59919?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-59919, 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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