CVE-2026-5450

CRITICALPre-NVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-04-20. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Elevated
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 9.8Exploit: Elevated riskExposed: 0

A fix is available — apply it.

Calling the scanf family of functions with a %mc (malloc'd character match) in the GNU C Library version 2.7 to version 2.43 with a format width specifier with an explicit width greater than 1024 could result in a one byte heap buffer overflow.

CVSS v3
9.8
EG Score
9.8(medium)
EG Risk
75(Attend)
EG Risk 75/100SSVC: Attend

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
Severity98% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
1%
EPSS %ILE
42%
KEV
Not listed

Published

April 20, 2026

Last Modified

July 14, 2026

Advisory Details (3)

Auto-updated Sep 12, 2026
⚠️ Active exploitation confirmed. No patch confirmed yet.
generic

34008 – (CVE-2026-5450) stdio-common: scanf %mc pattern will cause heap overflow when width > 1024

https://sourceware.org/bugzilla/show_bug.cgi?id=CVE-2026-5450
generic🔴 Active Exploitation

SSA-082556

https://cert-portal.siemens.com/productcert/html/ssa-082556.html
generic

The GNU C Library security advisories update for 2026-04-20

https://inbox.sourceware.org/libc-announce/[email protected]/T/#u

Vendor Advisories for CVE-2026-5450(20)

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

Patch Availability(23)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatrhosdt/opentelemetry-rhel9-operator:17857045472026-08-04redhat
redhatrhcos-414.92.202607210313-02026-07-31redhat
redhatrhcos-415.92.202607210244-02026-07-31redhat
redhatdiscovery/discovery-ui-rhel9:17848217502026-07-27redhat
redhatrhui5/rhua-rhel9:17847950762026-07-23redhat
redhatrhcos-413.92.202607141229-02026-07-23redhat
redhatrhcos-4.19.9.6.202607151909-02026-07-22redhat
redhatcostmanagement/costmanagement-metrics-rhel9-operator:17835391562026-07-15redhat
redhatcompat-glibc-1:2.12-4.el7_9.12026-07-09redhat
redhatglibc-0:2.12-1.212.el6_10.42026-07-09redhat
redhatglibc-0:2.28-151.el8_4.62026-07-08redhat
redhatinsights-proxy/insights-proxy-container-rhel9:17828905032026-07-01redhat
redhatglibc-0:2.17-326.el7_9.62026-07-01redhat
redhatglibc-0:2.39-126.el10_22026-06-30redhat
redhatglibc-0:2.39-46.el10_0.52026-06-29redhat
redhatglibc-0:2.34-272.el9_82026-06-29redhat
redhatglibc-0:2.28-225.el8_8.172026-06-29redhat
redhatglibc-0:2.34-60.el9_2.202026-06-29redhat
redhatglibc-0:2.28-189.13.el8_62026-06-29redhat
redhatglibc-0:2.28-251.el8_10.382026-06-29redhat
redhatglibc-0:2.34-168.el9_6.252026-06-29redhat
redhatglibc-0:2.34-100.el9_4.132026-06-29redhat
redhatglibc-main-2.42-12.hum12026-05-01redhat

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

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
glibc2.31-13 ... 2.43-2 (208 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
glibc2.36-10~0 ... 2.44-1 (130 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
glibc2.41-12 ... 2.44-1 (36 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
glibc2.41-12 ... 2.42-9 (24 versions)2.42-17—

Weakness Classification(2)

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

Additional Vendor Advisories

(9)

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 6× in last 7d / 25× 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 355 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-5450?
CVE-2026-5450 is a critical vulnerability published on April 20, 2026. Calling the scanf family of functions with a %mc (malloc'd character match) in the GNU C Library version 2.7 to version 2.43 with a format width specifier with an explicit width greater than 1024 could result in a one byte heap buffer overflow.
When was CVE-2026-5450 disclosed?
CVE-2026-5450 was first published in the National Vulnerability Database on April 20, 2026, with the most recent update on July 14, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-5450 actively exploited?
CVE-2026-5450 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 58.0% of all scored CVEs.
What is the CVSS score of CVE-2026-5450?
CVE-2026-5450 has a CVSS v3.1 base score of 9.8 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-5450?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-5450, 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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