7.8

CVE-2024-36904: debian debian_linux Use After Free

CVSS: 7.8v3.1HighModified
AliasesUBUNTU-CVE-2024-36904DEBIAN-CVE-2024-36904
Published 30-05-2024Last modified 15-10-2026
Open JSON

Vulnerability summary

CVE-2024-36904 is a high (CVSS 7.8) Use After Free vulnerability in debian debian_linux. EPSS estimates a 0.61% chance of exploitation in the next 30 days, higher than 48.3% of scored vulnerabilities.

Overall risk
31/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.8/10
010
High · v3.1 (CVE.org)
EPSS score
0.61%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 112 · Related 100
DLA-3840-1DLA-3843-1DSA-5703-1MGASA-2024-0263MGASA-2024-0266RHSA-2024:4583

Showing 100 of 112. Use Open JSON for the complete list.

Timeline

  1. 30-05-2024
    PublishedVulnerability first disclosed.
  2. 15-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: tcp: Use refcount_inc_not_zero() in tcp_twsk_unique(). Anderson Nascimento reported a use-after-free splat in tcp_twsk_unique() with nice analysis. Since commit ec94c2696f0b ("tcp/dccp: avoid one atomic operation for timewait hashdance"), inet_twsk_hashdance() sets TIME-WAIT socket's sk_refcnt after putting it into ehash and releasing the bucket lock. Thus, there is a small race window where other threads could try to reuse the port during connect() and call sock_hold() in tcp_twsk_unique() for the TIME-WAIT socket with zero refcnt. If that happens, the refcnt taken by tcp_twsk_unique() is overwritten and sock_put() will cause underflow, triggering a real use-after-free somewhere else. To avoid the use-after-free, we need to use refcount_inc_not_zero() in tcp_twsk_unique() and give up on reusing the port if it returns false. [0]: refcount_t: addition on 0; use-after-free. WARNING: CPU: 0 PID: 1039313 at lib/refcount.c:25 refcount_warn_saturate+0xe5/0x110 CPU: 0 PID: 1039313 Comm: trigger Not tainted 6.8.6-200.fc39.x86_64 #1 Hardware name: VMware, Inc. VMware20,1/440BX Desktop Reference Platform, BIOS VMW201.00V.21805430.B64.2305221830 05/22/2023 RIP: 0010:refcount_warn_saturate+0xe5/0x110 Code: 42 8e ff 0f 0b c3 cc cc cc cc 80 3d aa 13 ea 01 00 0f 85 5e ff ff ff 48 c7 c7 f8 8e b7 82 c6 05 96 13 ea 01 01 e8 7b 42 8e ff <0f> 0b c3 cc cc cc cc 48 c7 c7 50 8f b7 82 c6 05 7a 13 ea 01 01 e8 RSP: 0018:ffffc90006b43b60 EFLAGS: 00010282 RAX: 0000000000000000 RBX: ffff888009bb3ef0 RCX: 0000000000000027 RDX: ffff88807be218c8 RSI: 0000000000000001 RDI: ffff88807be218c0 RBP: 0000000000069d70 R08: 0000000000000000 R09: ffffc90006b439f0 R10: ffffc90006b439e8 R11: 0000000000000003 R12: ffff8880029ede84 R13: 0000000000004e20 R14: ffffffff84356dc0 R15: ffff888009bb3ef0 FS: 00007f62c10926c0(0000) GS:ffff88807be00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020ccb000 CR3: 000000004628c005 CR4: 0000000000f70ef0 PKRU: 55555554 Call Trace: <TASK> ? refcount_warn_saturate+0xe5/0x110 ? __warn+0x81/0x130 ? refcount_warn_saturate+0xe5/0x110 ? report_bug+0x171/0x1a0 ? refcount_warn_saturate+0xe5/0x110 ? handle_bug+0x3c/0x80 ? exc_invalid_op+0x17/0x70 ? asm_exc_invalid_op+0x1a/0x20 ? refcount_warn_saturate+0xe5/0x110 tcp_twsk_unique+0x186/0x190 __inet_check_established+0x176/0x2d0 __inet_hash_connect+0x74/0x7d0 ? __pfx___inet_check_established+0x10/0x10 tcp_v4_connect+0x278/0x530 __inet_stream_connect+0x10f/0x3d0 inet_stream_connect+0x3a/0x60 __sys_connect+0xa8/0xd0 __x64_sys_connect+0x18/0x20 do_syscall_64+0x83/0x170 entry_SYSCALL_64_after_hwframe+0x78/0x80 RIP: 0033:0x7f62c11a885d Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a3 45 0c 00 f7 d8 64 89 01 48 RSP: 002b:00007f62c1091e58 EFLAGS: 00000296 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 0000000020ccb004 RCX: 00007f62c11a885d RDX: 0000000000000010 RSI: 0000000020ccb000 RDI: 0000000000000003 RBP: 00007f62c1091e90 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 00007f62c10926c0 R13: ffffffffffffff88 R14: 0000000000000000 R15: 00007ffe237885b0 </TASK>

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.61%

Chance of exploitation in the next 30 days

Percentile

48%

Versus all other CVEs

30-day change

0.00 pp

From 0.61% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.61%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ubuntu124 products
  • linux< 5.4.0-192.212 | < 5.15.0-118.128 | < 6.8.0-40.40
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 5.4.0-1130.140 | < 5.15.0-1067.73 | < 6.8.0-1013.14
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian2 products
Linux2 products
  • linux≥ ec94c2696f0bcd5ae92a553244e4ac30d2171a2d, < 84546cc1aeeb4df3e444b18a4293c9823f974be9 | ≥ ec94c2696f0bcd5ae92a553244e4ac30d2171a2d, < 1796ca9c6f5bd50554214053af5f47d112818ee3 | ≥ ec94c2696f0bcd5ae92a553244e4ac30d2171a2d, < 1d9cf07810c30ef7948879567d10fd1f01121d34 | ≥ ec94c2696f0bcd5ae92a553244e4ac30d2171a2d, < 27b0284d8be182a81feb65581ab6a724dfd596e8 | ≥ ec94c2696f0bcd5ae92a553244e4ac30d2171a2d, < 13ed7cdf079686ccd3618335205700c03f6fb446 | ≥ ec94c2696f0bcd5ae92a553244e4ac30d2171a2d, < 6e48faad92be13166184d21506e4e54c79c13adc | ≥ ec94c2696f0bcd5ae92a553244e4ac30d2171a2d, < 517e32ea0a8c72202d0d8aa8df50a7cd3d6fdefc | ≥ ec94c2696f0bcd5ae92a553244e4ac30d2171a2d, < f2db7230f73a80dbb179deab78f88a7947f0ab7e | 4.16
  • linux_kernel≥ 4.16, < 4.19.314 | ≥ 4.20, < 5.4.276 | ≥ 5.5, < 5.10.217 | ≥ 5.11, < 5.15.159 | ≥ 5.16, < 6.1.91 | ≥ 6.2, < 6.6.31 | ≥ 6.7, < 6.8.10 | 6.9:rc1 | 6.9:rc2 | 6.9:rc3 | 6.9:rc4 | 6.9:rc5 | 6.9:rc6 | 6.9:rc7

3 vendors · 128 products

References

36 links
Show all 36 references