7.8

CVE-2024-44939: jfs: fix null ptr deref in dtInsertEntry

Modified
AliasesUBUNTU-CVE-2024-44939DEBIAN-CVE-2024-44939
Published 26-08-2024Last modified 05-08-2026

Vulnerability summary

CVE-2024-44939 is a high (CVSS 7.8) NULL Pointer Dereference vulnerability in linux. EPSS estimates a 0.23% chance of exploitation in the next 30 days, higher than 14.4% 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
0.23%
0%100%
Low · 0.00 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 26 · Related 22
DLA-4008-1DSA-5782-1MGASA-2024-0309MGASA-2024-0310SUSE-SU-2024:3190-1SUSE-SU-2024:3194-1

Timeline

  1. 26-08-2024
    PublishedVulnerability first disclosed.
  2. 05-08-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: jfs: fix null ptr deref in dtInsertEntry [syzbot reported] general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 0 PID: 5061 Comm: syz-executor404 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:dtInsertEntry+0xd0c/0x1780 fs/jfs/jfs_dtree.c:3713 ... [Analyze] In dtInsertEntry(), when the pointer h has the same value as p, after writing name in UniStrncpy_to_le(), p->header.flag will be cleared. This will cause the previously true judgment "p->header.flag & BT-LEAF" to change to no after writing the name operation, this leads to entering an incorrect branch and accessing the uninitialized object ih when judging this condition for the second time. [Fix] After got the page, check freelist first, if freelist == 0 then exit dtInsert() and return -EINVAL.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.23%

Chance of exploitation in the next 30 days

Percentile

14%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.23% 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.

Ubuntu129 products
  • linuxAll versions (No fix recorded) | < 5.15.0-156.166 | < 6.8.0-50.51
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 5.15.0-1092.99 | < 6.8.0-1020.22
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < f98bf80b20f4a930589cda48a35f751a64fe0dc2 | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 53023ab11836ac56fd75f7a71ec1356e50920fa9 | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 6ea10dbb1e6c58384136e9adfd75f81951e423f6 | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 9c2ac38530d1a3ee558834dfa16c85a40fd0e702 | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < ce6dede912f064a855acf6f04a04cbb2c25b8c8c | 2.6.12
  • linux_kernel< 6.6.47 | ≥ 6.7, < 6.10.6
Debian1 product
  • linux< 6.1.112-1 | < 6.10.6-1

3 vendors · 132 products

References

24 links
Show all 24 references