CVE-2025-55639

MEDIUMPre-NVD 6.56.5
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to the CVSS score beside it.

Score 6.5 from GitHub Security Advisory published 2026-06-23. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 6.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: CISA-ADP (Vulnrichment) CVSS v3.1, EPSS, GitHub Security Advisory
Trending — 3 sources updated this weekElevated

Also known asEUVD-2025-210311 (ENISA EUVD) · GHSA-hr6c-43h9-9ghm (GitHub Security Advisories)Source: ENISA EUVD

6.5EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (the SSVC decision on this page).
  • CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
CISA-KEV: Not listedEPSS PROB: 0.5%CVSS: 6.5Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

GPAC MP4Box v2.4 was discovered to contain a NULL pointer dereference in the gf_isom_add_track_kind() function at isomedia/isom_write.c. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted MP4 file.

CVSS v3
6.5
EG Score
6.5MEDIUMmedium confidence
EG Risk
45
EG Risk 45/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity65% × 45%
Impact severity (EG Severity): CVSS 6.5 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Track* at high (mission-essential systems).
Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.5%
EPSS %ILE
43rd
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (6.5): severity, escalated by confirmed exploitation. This CVE's 6.5 is its impact severity (EG Severity), not escalated.

EG Severity
6.5 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.5% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-24). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at low or medium mission impact; Track* at high (mission-essential systems).CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines.

Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

June 23, 2026

Last Modified

October 12, 2026

Advisory Details (4)

Auto-updated Jun 23, 2026
Patch available. Sources: github_commit.
Web page

sigdevel: "Security Advisory: CVE-2025-55639 - NULL Pointer …" - Infosec Exchange

https://infosec.exchange/@sigdevel/116769184815236865
GitHub commit Patch Available

commit 027ce139dda4 (gpac/gpac)

Patch available: gpac/gpac v26.02.0 (contains commit 027ce139dda4)

https://github.com/gpac/gpac/commit/027ce139dda498ee95df36db9f9f6f3cadce8ec9
Web page

pocs/res/gpac/MP4Box/23/23_poc.mp4 at main · sigdevel/pocs · GitHub

https://github.com/sigdevel/pocs/blob/main/res/gpac/MP4Box/23/23_poc.mp4
Web page

[security] isomedia/isom_write.c:3153 null-pointer dereference in gf_isom_add_track_kind · Issue #3260 · gpac/gpac · GitHub

https://github.com/gpac/gpac/issues/3260

Vendor Advisories for CVE-2025-55639(1)

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

Affected Packages

(1 across 1 ecosystem)
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
gpac1.0.1+dfsg1-4 ... 2.2.1+dfsg1-3.1~exp1 (13 versions)
  • every version on: no fix on record
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 9× in last 7d / 39× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 96 of 234 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. 4 repeat rows among the latest 100 are merged into the row they repeat. The 138 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-30 16:33 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  2. 2026-10-29 16:31 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  3. 2026-10-28 16:30 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  4. 2026-10-27 16:30 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  5. 2026-10-27 10:55 UTCOSV refresh
  6. 2026-10-26 16:30 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  7. 2026-10-25 16:31 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  8. 2026-10-25 16:17 UTCEG score recompute
  9. 2026-10-24 16:31 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  10. 2026-10-23 16:30 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  11. 2026-10-22 16:33 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  12. 2026-10-21 16:31 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  13. 2026-10-20 16:31 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  14. 2026-10-19 16:31 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  15. 2026-10-18 16:31 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  16. 2026-10-18 05:25 UTCEG score recompute
  17. 2026-10-17 16:33 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  18. 2026-10-16 16:39 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  19. 2026-10-15 16:31 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  20. 2026-10-14 16:31 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  21. 2026-10-13 16:33 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  22. 2026-10-12 21:28 UTCGHSA enrichmentGHSA-hr6c-43h9-9ghm · GitHub CVSS 6.5
  23. 2026-10-12 16:56 UTCEG score recompute
  24. 2026-10-12 16:33 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  25. 2026-10-11 20:29 UTCEG score recompute
Show 71 more
  1. 2026-10-11 18:41 UTCEG score recompute
  2. 2026-10-11 15:16 UTCEG score recompute
  3. 2026-10-11 13:47 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  4. 2026-10-10 19:59 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  5. 2026-10-09 20:06 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  6. 2026-10-08 17:10 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  7. 2026-10-07 23:47 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  8. 2026-10-06 15:17 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  9. 2026-10-05 17:42 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  10. 2026-10-05 16:29 UTCEG score recompute
  11. 2026-10-05 16:29 UTCGHSA enrichmentGHSA-hr6c-43h9-9ghm · GitHub CVSS 6.5
  12. 2026-10-04 23:21 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  13. 2026-10-03 14:24 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  14. 2026-10-01 19:49 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  15. 2026-09-30 15:02 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  16. 2026-09-28 13:50 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  17. 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  18. 2026-09-26 00:25 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  19. 2026-09-24 14:02 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  20. 2026-09-23 13:47 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  21. 2026-09-21 21:06 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  22. 2026-09-20 20:15 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  23. 2026-09-19 15:42 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  24. 2026-09-18 19:27 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  25. 2026-09-18 11:12 UTCEG score recompute
  26. 2026-09-18 11:12 UTCGHSA enrichmentGHSA-hr6c-43h9-9ghm · GitHub CVSS 6.5
  27. 2026-09-17 19:29 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  28. 2026-09-16 14:07 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  29. 2026-09-16 05:14 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  30. 2026-09-13 16:46 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  31. 2026-09-13 12:28 UTCEG score recompute
  32. 2026-09-13 12:28 UTCGHSA enrichmentGHSA-hr6c-43h9-9ghm · GitHub CVSS 6.5
  33. 2026-09-12 15:00 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  34. 2026-09-11 14:52 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  35. 2026-09-11 09:36 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  36. 2026-09-10 09:34 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  37. 2026-09-08 21:59 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  38. 2026-09-07 16:00 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  39. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  40. 2026-09-05 15:28 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  41. 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  42. 2026-09-02 14:11 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  43. 2026-09-01 13:53 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  44. 2026-09-01 04:38 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  45. 2026-08-30 20:28 UTCEG score recompute
  46. 2026-08-30 20:28 UTCGHSA enrichmentGHSA-hr6c-43h9-9ghm · GitHub CVSS 6.5
  47. 2026-08-30 19:16 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  48. 2026-08-30 01:21 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  49. 2026-08-28 21:40 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  50. 2026-08-27 14:24 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  51. 2026-08-26 14:45 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  52. 2026-08-25 13:48 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  53. 2026-08-24 14:16 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  54. 2026-08-24 13:55 UTCEG score recompute
  55. 2026-08-24 13:55 UTCGHSA enrichmentGHSA-hr6c-43h9-9ghm · GitHub CVSS 6.5
  56. 2026-08-24 09:22 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  57. 2026-08-23 13:35 UTCEG score recompute
  58. 2026-08-23 13:35 UTCGHSA enrichmentGHSA-hr6c-43h9-9ghm · GitHub CVSS 6.5
  59. 2026-08-23 00:18 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  60. 2026-08-22 14:53 UTCEG score recompute
  61. 2026-08-22 14:53 UTCGHSA enrichmentGHSA-hr6c-43h9-9ghm · GitHub CVSS 6.5
  62. 2026-08-21 23:48 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  63. 2026-08-21 06:32 UTCEG score recompute
  64. 2026-08-21 06:32 UTCGHSA enrichmentGHSA-hr6c-43h9-9ghm · GitHub CVSS 6.5
  65. 2026-08-20 22:54 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  66. 2026-08-20 07:49 UTCEG score recompute
  67. 2026-08-20 07:49 UTCGHSA enrichmentGHSA-hr6c-43h9-9ghm · GitHub CVSS 6.5
  68. 2026-08-19 17:03 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  69. 2026-08-19 04:50 UTCEG score recompute
  70. 2026-08-19 04:50 UTCGHSA enrichmentGHSA-hr6c-43h9-9ghm · GitHub CVSS 6.5
  71. 2026-08-18 13:47 UTCEPSS rescoreEPSS 0.4% · 31st percentile

Frequently asked(5)

What is CVE-2025-55639?
CVE-2025-55639 is a medium-severity vulnerability; its CVE record was published on June 23, 2026. GPAC MP4Box v2.4 was discovered to contain a NULL pointer dereference in the gfisomaddtrackkind() function at isomedia/isom_write.c. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted MP4 file.
When was the CVE record for CVE-2025-55639 published?
The CVE record for CVE-2025-55639 was published on June 23, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of October 12, 2026; the record at its source may have been updated since.
Is CVE-2025-55639 actively exploited?
CVE-2025-55639 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.5% probability of exploitation in the next 30 days (43rd percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2025-55639?
CVE-2025-55639 has a CVSS v3.1 base score of 6.5 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2025-55639?
A fix for CVE-2025-55639 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2025-55639 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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