7.8

CVE-2026-43278: dm: clear cloned request bio pointer when last clone bio completes

Modified
AliasesUBUNTU-CVE-2026-43278DEBIAN-CVE-2026-43278
Published 06-05-2026Last modified 19-10-2026

Vulnerability summary

CVE-2026-43278 is a high (CVSS 7.8) Double Free vulnerability in linux. EPSS estimates a 0.12% chance of exploitation in the next 30 days, higher than 1.6% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 7.8, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
7.8/10
010
High · v3.1 (CVE.org)
EPSS score
0.12%
0%100%
Low · -0.05 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 25 · Related 24
LSN-0122-1OPENSUSE-SU-2026:21555-1SUSE-SU-2026:23066-1SUSE-SU-2026:23068-1SUSE-SU-2026:23221-1SUSE-SU-2026:23231-1

Timeline

  1. 06-05-2026
    PublishedVulnerability first disclosed.
  2. 19-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: dm: clear cloned request bio pointer when last clone bio completes Stale rq->bio values have been observed to cause double-initialization of cloned bios in request-based device-mapper targets, leading to use-after-free and double-free scenarios. One such case occurs when using dm-multipath on top of a PCIe NVMe namespace, where cloned request bios are freed during blk_complete_request(), but rq->bio is left intact. Subsequent clone teardown then attempts to free the same bios again via blk_rq_unprep_clone(). The resulting double-free path looks like: nvme_pci_complete_batch() nvme_complete_batch() blk_mq_end_request_batch() blk_complete_request() // called on a DM clone request bio_endio() // first free of all clone bios ... rq->end_io() // end_clone_request() dm_complete_request(tio->orig) dm_softirq_done() dm_done() dm_end_request() blk_rq_unprep_clone() // second free of clone bios Fix this by clearing the clone request's bio pointer when the last cloned bio completes, ensuring that later teardown paths do not attempt to free already-released bios.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.12%

Chance of exploitation in the next 30 days

Percentile

2%

Versus all other CVEs

30-day change

Decrease -0.05 pp

From 0.17% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu130 products
  • linux< 6.8.0-134.134 | All versions (No fix recorded)
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 6.8.0-1060.63 | All versions (No fix recorded)
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ ab3e1d3bbab9e973aeb4dd4603251578658a47ff, < 8d9ddad561136f7e6a9346767bf97b4d79e38e67 | ≥ ab3e1d3bbab9e973aeb4dd4603251578658a47ff, < 7daf279c674d515fb22a727a7bbc92aeb35c5442 | ≥ ab3e1d3bbab9e973aeb4dd4603251578658a47ff, < e2e738e8dfbbf83bd2bae0467ec4420cc52da42a | ≥ ab3e1d3bbab9e973aeb4dd4603251578658a47ff, < b1c1a2637ebd675aa2d71fee8c70da8791d73850 | ≥ ab3e1d3bbab9e973aeb4dd4603251578658a47ff, < 83d72091804600ead96dc9e9f518ea56cb4942f6 | ≥ ab3e1d3bbab9e973aeb4dd4603251578658a47ff, < fb8a6c18fb9a6561f7a15b58b272442b77a242dd | 6.1
  • linux_kernel≥ 6.1, < 6.1.165 | ≥ 6.2, < 6.6.128 | ≥ 6.7, < 6.12.75 | ≥ 6.13, < 6.18.16 | ≥ 6.19, < 6.19.6
Debian1 product
  • linux< 6.1.170-1 | < 6.12.85-1 | < 6.19.6-1

3 vendors · 133 products

References

24 links
Show all 24 references