CVE-2024-23638

MEDIUMNVD 6.56.5—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.5 under NVD CVSS v3. EPSS exploit probability: 60.1%, top 1% 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, nvd
Weaponized
6.5
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • High exploitation likelihood — EPSS 60%
CISA-KEV: Not listedEPSS: 60%CVSS: 6.5Exploit: NoneExposed: 0

A fix is available — apply it.

Squid is a caching proxy for the Web. Due to an expired pointer reference bug, Squid prior to version 6.6 is vulnerable to a Denial of Service attack against Cache Manager error responses. This problem allows a trusted client to perform Denial of Service when generating error pages for Client Manager reports. Squid older than 5.0.5 have not been tested and should be assumed to be vulnerable. All Squid-5.x up to and including 5.9 are vulnerable. All Squid-6.x up to and including 6.5 are vulnerable. This bug is fixed by Squid version 6.6. In addition, patches addressing this problem for the stable releases can be found in Squid's patch archives. As a workaround, prevent access to Cache Manager using Squid's main access control: http_access deny manager.

CVSS v3
6.5
EG Score
6.5(medium)
EG Risk
—
EPSS
99.0%
KEV
Not listed

Published

January 24, 2024

Last Modified

November 21, 2024

References (18)

Patch Availability(3)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntusquidclient (6.1-2ubuntu1.3) @ mantic2026-05-24ubuntu
redhatsquid:4-8100020241113143337.489197e62024-11-14redhat
redhatsquid-7:5.5-13.el9_42024-07-25redhat

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.

Weakness Classification(2)

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

All Vendor Advisories

(3)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 7× 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.

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

Frequently asked(5)

What is CVE-2024-23638?
CVE-2024-23638 is a medium vulnerability published on January 24, 2024. Squid is a caching proxy for the Web. Due to an expired pointer reference bug, Squid prior to version 6.6 is vulnerable to a Denial of Service attack against Cache Manager error responses. This problem allows a trusted client to perform Denial of Service when generating error pages for Client…
When was CVE-2024-23638 disclosed?
CVE-2024-23638 was first published in the National Vulnerability Database on January 24, 2024, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2024-23638 actively exploited?
CVE-2024-23638 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 99.0% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2024-23638?
CVE-2024-23638 has a CVSS v3 base score of 6.5 (NVD).
How do I remediate CVE-2024-23638?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2024-23638, 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

Explore the affected products and dependency analysis for CVE-2024-23638

Explore →

Is Your Infrastructure Affected by CVE-2024-23638?

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

Start Free Scan →Browse All CVEs