CVE-2025-21887

HIGHPre-NVD 7.87.8—
EchelonGraph scoreMEDIUM confidence

Score 7.8 from GitHub Security Advisory (severity: HIGH) published 2025-03-27. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 7.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
7.8
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 7.8Exploit: NoneExposed: 0

A fix is available — apply it.

In the Linux kernel, the following vulnerability has been resolved:

ovl: fix UAF in ovl_dentry_update_reval by moving dput() in ovl_link_up

The issue was caused by dput(upper) being called before ovl_dentry_update_reval(), while upper->d_flags was still accessed in ovl_dentry_remote().

Move dput(upper) after its last use to prevent use-after-free.

BUG: KASAN: slab-use-after-free in ovl_dentry_remote fs/overlayfs/util.c:162 [inline] BUG: KASAN: slab-use-after-free in ovl_dentry_update_reval+0xd2/0xf0 fs/overlayfs/util.c:167

Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 print_address_description mm/kasan/report.c:377 [inline] print_report+0xc3/0x620 mm/kasan/report.c:488 kasan_report+0xd9/0x110 mm/kasan/report.c:601 ovl_dentry_remote fs/overlayfs/util.c:162 [inline] ovl_dentry_update_reval+0xd2/0xf0 fs/overlayfs/util.c:167 ovl_link_up fs/overlayfs/copy_up.c:610 [inline] ovl_copy_up_one+0x2105/0x3490 fs/overlayfs/copy_up.c:1170 ovl_copy_up_flags+0x18d/0x200 fs/overlayfs/copy_up.c:1223 ovl_rename+0x39e/0x18c0 fs/overlayfs/dir.c:1136 vfs_rename+0xf84/0x20a0 fs/namei.c:4893 ...

CVSS v3
7.8
EG Score
7.8(medium)
EG Risk
35(Track)
EG Risk 35/100SSVC: 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
Severity78% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS
8.3%
KEV
Not listed

Published

March 27, 2025

Last Modified

July 14, 2026

Advisory Details (9)

Auto-updated Jul 14, 2026
Patch available.
generic

SSA-019113

https://cert-portal.siemens.com/productcert/html/ssa-019113.html
generic Patch Available

[SECURITY] [DLA 4193-1] linux-6.1 security update

https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html
generic

ovl: fix UAF in ovl_dentry_update_reval by moving dput() in ovl_link_up - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/f77618291836168eca99e89cd175256f928f5e64
generic

ovl: fix UAF in ovl_dentry_update_reval by moving dput() in ovl_link_up - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/c84e125fff2615b4d9c259e762596134eddd2f27
generic

ovl: fix UAF in ovl_dentry_update_reval by moving dput() in ovl_link_up - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/a7c41830ffcd17b2177a95a9b99b270302090c35
generic

ovl: fix UAF in ovl_dentry_update_reval by moving dput() in ovl_link_up - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/64455c8051c3aedc71abb7ec8d47c80301f99f00
generic

ovl: fix UAF in ovl_dentry_update_reval by moving dput() in ovl_link_up - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/60b4b5c1277fc491da9e1e7abab307bfa39c2db7
generic

ovl: fix UAF in ovl_dentry_update_reval by moving dput() in ovl_link_up - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/4b49d939b5a79117f939b77cc67efae2694d9799
generic

ovl: fix UAF in ovl_dentry_update_reval by moving dput() in ovl_link_up - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/3594aad97e7be2557ca9fa9c931b206b604028c8

Vendor Advisories for CVE-2025-21887(5)

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

Patch Availability(28)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-tools-gcp-lts-22.04 (5.15.0.1083.79) @ jammy2026-05-30ubuntu
ubuntulinux-tools-gcp-fips (5.15.0.1083.73) @ jammy2026-05-30ubuntu
ubuntulinux-virtual-hwe-24.04-edge (6.11.0-26.26~24.04.1) @ noble2026-05-30ubuntu
ubuntulinux-tools-oracle-64k (6.11.0-1016.17) @ oracular2026-05-30ubuntu
ubuntulinux-tools-gke-5.15 (5.15.0.1081.80) @ jammy2026-05-30ubuntu
ubuntulinux-tools-aws (6.11.0-1014.15) @ oracular2026-05-30ubuntu
ubuntulinux-tools-azure-fips (5.15.0.1089.74) @ jammy2026-05-30ubuntu
ubuntulinux-tools-aws-fips (5.15.0.1084.80) @ jammy2026-05-30ubuntu
ubuntulinux-tools-raspi-nolpae (5.15.0.1078.76) @ jammy2026-05-30ubuntu
ubuntulinux-tools-realtime (5.15.0.1084.88) @ jammy2026-05-30ubuntu
ubuntulinux-tools-nvidia-tegra-rt (5.15.0.1037.37) @ jammy2026-05-30ubuntu
ubuntulinux-tools-aws-edge (5.15.0.1084.91~20.04.1) @ focal2026-05-30ubuntu
ubuntuoracle (6.8.0-1005) @ noble2026-05-30ubuntu
ubuntulinux-virtual-hwe-20.04-edge (5.15.0.142.152~20.04.1) @ focal2026-05-30ubuntu
ubuntulinux-xilinx-zynqmp-tools-host (5.15.0-1050.54) @ jammy2026-05-30ubuntu
ubuntulinux-tools-oracle-edge (6.8.0-1033.34~22.04.1) @ jammy2026-05-30ubuntu
ubuntuoracle (5.15.0-1055) @ jammy2026-05-30ubuntu
ubuntulinux-tools-ibm-lts-24.04 (6.8.0-1037.37) @ noble2026-05-30ubuntu
ubuntulinux-tools-azure-nvidia-lts-24.04 (6.8.0-1025.27) @ noble2026-05-30ubuntu
ubuntulinux-tools-realtime-6.8.1 (6.8.1-1031.32) @ noble2026-05-30ubuntu
ubuntulinux-tools-raspi-6.8 (6.8.0-1036.40) @ noble2026-05-30ubuntu
ubuntulinux-virtual-hwe-20.04-edge (5.15.0.140.135) @ jammy2026-05-30ubuntu
ubuntulinux-tools-azure-lts-24.04 (6.8.0-1038.44) @ noble2026-05-30ubuntu
ubuntulinux-tools-fips (5.15.0.140.80) @ jammy2026-05-30ubuntu
ubuntulinux-tools-gcp-edge (5.15.0.1083.92~20.04.1) @ focal2026-05-30ubuntu
redhatkernel-0:5.14.0-427.79.1.el9_42025-07-28redhat
redhatkernel-0:5.14.0-570.25.1.el9_62025-07-07redhat
redhatkernel-0:6.12.0-55.17.1.el10_02025-06-16redhat

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(1)

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

Additional Vendor Advisories

(21)

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

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2025-21887?
CVE-2025-21887 is a high vulnerability published on March 27, 2025. In the Linux kernel, the following vulnerability has been resolved: ovl: fix UAF in ovldentryupdatereval by moving dput() in ovllink_up The issue was caused by dput(upper) being called before ovldentryupdatereval(), while upper->dflags was still accessed in ovldentryremote(). Move dput(upper) after…
When was CVE-2025-21887 disclosed?
CVE-2025-21887 was first published in the National Vulnerability Database on March 27, 2025, 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-2025-21887 actively exploited?
CVE-2025-21887 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 8.3% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2025-21887?
CVE-2025-21887 has a CVSS v3.1 base score of 7.8 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2025-21887?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2025-21887, 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-2025-21887

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