CVE-2026-5081

CRITICALPre-NVD 9.19.1—
EchelonGraph scoreMEDIUM confidence

Score 9.1 from GitHub Security Advisory (severity: CRITICAL) published 2026-05-06. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 9.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
9.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 9.1Exploit: None knownExposed: 0

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

Apache::Session::Generate::ModUniqueId versions from 1.54 through 1.94 for Perl session ids are insecure.

Apache::Session::Generate::ModUniqueId (added in version 1.54) uses the value of the UNIQUE_ID environment variable for the session id. The UNIQUE_ID variable is set by the Apache mod_unique_id plugin, which generates unique ids for the request. The id is based on the IPv4 address, the process id, the epoch time, a 16-bit counter and a thread index, with no obfuscation.

The server IP is often available to the public, and if not available, can be guessed from previous session ids being issued. The process ids may also be guessed from previous session ids. The timestamp is easily guessed (and leaked in the HTTP Date response header).

The purpose of mod_unique_id is to assign a unique id to requests so that events can be correlated in different logs. The id is not designed, nor is it suitable for security purposes.

CVSS v3
9.1
EG Score
9.1(medium)
EG Risk
56(Track)
EG Risk 56/100SSVC: 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
Severity91% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
23%
KEV
Not listed

Published

May 6, 2026

Last Modified

July 15, 2026

Advisory Details (6)

Auto-updated Sep 7, 2026
Patch available. Sources: redhat.
redhat
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-5081.json
redhat

2467174 – (CVE-2026-5081) CVE-2026-5081 Apache::Session::Generate::ModUniqueId: Perl: mod_unique_id: Apache HTTP Server: Apache::Session::Generate::ModUniqueId: Session ID predictability allows unauthorized access

https://bugzilla.redhat.com/show_bug.cgi?id=2467174
redhat Patch Available

CVE-2026-5081 - Red Hat Customer Portal

Affected: Red Hat Enterprise Linux 8 or OpenShift Container Platform 4, is affected by this vulnerability and a fix may be released to a

https://access.redhat.com/security/cve/CVE-2026-5081
generic

oss-security - CVE-2026-5081: Apache::Session::Generate::ModUniqueId versions from 1.54 through 1.94 for Perl session ids are insecure

http://www.openwall.com/lists/oss-security/2026/05/06/6
generic

Apache::Session::Generate::Random - use system randomness for generating session ids - metacpan.org

https://metacpan.org/pod/Apache::Session::Generate::Random
generic

mod_unique_id - Apache HTTP Server Version 2.4

https://httpd.apache.org/docs/current/mod/mod_unique_id.html

Vendor Advisories for CVE-2026-5081(1)

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

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
libapache-session-perl1.94-1, 1.94-2——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
libapache-session-perl1.94-2——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
libapache-session-perl1.94-2——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
libapache-session-perl1.94-2——

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 5× in last 7d / 29× 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 275 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-5081?
CVE-2026-5081 is a critical vulnerability published on May 6, 2026. Apache::Session::Generate::ModUniqueId versions from 1.54 through 1.94 for Perl session ids are insecure. Apache::Session::Generate::ModUniqueId (added in version 1.54) uses the value of the UNIQUEID environment variable for the session id. The UNIQUEID variable is set by the Apache moduniqueid…
When was CVE-2026-5081 disclosed?
CVE-2026-5081 was first published in the National Vulnerability Database on May 6, 2026, with the most recent update on July 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-5081 actively exploited?
CVE-2026-5081 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 77.2% of all scored CVEs.
What is the CVSS score of CVE-2026-5081?
CVE-2026-5081 has a CVSS v3.1 base score of 9.1 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-5081?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-5081, 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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