CVE-2026-71973

MEDIUMPre-NVD 5.25.2—
EchelonGraph scoreHIGH confidence

Score 5.2 from GitHub Security Advisory published 2026-09-30. A secondary CVSS source baseline 5.2; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 5 sources updated this week
5.2EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS: 5.2Exploit: None knownExposed services: Not assessed

An upstream fix is merged but not yet released — mitigate (WAF / firewall / segmentation) until the release ships, then apply it.

U-Boot before 2026.10-rc4 contains an integer overflow vulnerability in sqfs_read_directory_table() function when allocating the directory table buffer. Attackers can supply a crafted SquashFS image with an attacker-controlled superblock metablks_count value that causes heap buffer under-allocation and out-of-bounds writes, corrupting heap memory and crashing the bootloader.

CVSS v3
5.2
EG Score
5.2MEDIUMhigh confidence
EG Risk
23
EG Risk 23/100CISA SSVC

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
Severity52% × 45%
Exploitation0% × 40%
Automatability0% × 15%
CISA SSVC: Track at every mission impact level.
Action: An upstream fix is merged but not yet in a tagged release. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines until it ships, then apply the release.
EPSS PROB
0.2%
EPSS %ILE
7th
KEV
Not listed

CISA SSVCTrack at every mission impact level.

An upstream fix is merged but not yet in a tagged release. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines until it ships, then apply the release.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

September 29, 2026

Last Modified

October 2, 2026

Advisory Details (4)

Auto-updated Sep 29, 2026
Upstream fix merged — awaiting tagged release. Sources: github_commit.
generic

U-Boot before 2026.10-rc4 Integer Overflow in SquashFS Directory Table Allocation | Advisories | VulnCheck

https://www.vulncheck.com/advisories/u-boot-before-2026.10-rc4-integer-overflow-in-squashfs-directory-table-allocation
generic

GitHub - u-boot/u-boot: "Das U-Boot" Source Tree · GitHub

https://github.com/u-boot/u-boot
generic

u-boot/fs/squashfs/sqfs.c at v2026.07 · u-boot/u-boot · GitHub

https://github.com/u-boot/u-boot/blob/v2026.07/fs/squashfs/sqfs.c#L814
github_commit

commit 561ae28cb56a (u-boot/u-boot)

Fix landed in u-boot/u-boot commit 561ae28cb56a — awaiting tagged release

https://github.com/u-boot/u-boot/commit/561ae28cb56a082cfa90c1c421c4955bc215470b

Vendor Advisories for CVE-2026-71973(2)

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

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 19× in last 7d / 19× 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. 2026-10-04 10:22 UTCEG score recompute
  2. 2026-10-04 10:22 UTCVendor advisory
  3. 2026-10-04 10:22 UTCGHSA enrichment
  4. 2026-10-03 14:26 UTCEPSS rescore
  5. 2026-10-03 11:50 UTCEG score recompute
  6. 2026-10-03 11:50 UTCVendor advisory
  7. 2026-10-03 11:50 UTCGHSA enrichment
  8. 2026-10-02 13:18 UTCEG score recompute
  9. 2026-10-02 13:18 UTCGHSA enrichment
  10. 2026-10-02 12:46 UTCEG score recompute
  11. 2026-10-02 12:46 UTCGHSA enrichment
  12. 2026-10-01 19:50 UTCEPSS rescore
  13. 2026-10-01 15:16 UTCGHSA enrichment
  14. 2026-09-30 16:45 UTCEG score recompute
  15. 2026-09-30 16:45 UTCGHSA enrichment
  16. 2026-09-30 15:03 UTCEPSS rescore
  17. 2026-09-29 22:25 UTCEG score recompute
  18. 2026-09-29 21:37 UTCEG score recompute
  19. 2026-09-29 21:33 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-71973?
CVE-2026-71973 is a medium vulnerability published on September 29, 2026. U-Boot before 2026.10-rc4 contains an integer overflow vulnerability in sqfsreaddirectorytable() function when allocating the directory table buffer. Attackers can supply a crafted SquashFS image with an attacker-controlled superblock metablkscount value that causes heap buffer under-allocation and…
When was CVE-2026-71973 disclosed?
CVE-2026-71973 was first published on September 29, 2026, with the most recent update on October 2, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-71973 actively exploited?
CVE-2026-71973 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (7th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-71973?
CVE-2026-71973 has a CVSS base score of 5.2 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-71973?
An upstream fix for CVE-2026-71973 has been merged but is not yet in a tagged release. Until it ships, restrict network exposure of the affected system or apply the vendor's mitigation, then update to the release that contains the fix. The vendor advisories EchelonGraph has for CVE-2026-71973 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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