Vulnerability in Linux
CVE-2024-26640
In the Linux kernel, the following vulnerability has been resolved: tcp: add sanity checks to rx zerocopy TCP rx zerocopy intent is to map pages initially allocated from NIC drivers, not pages owned by a fs. This patch adds to can_map_frag() these additional checks: - Page must not be a compound one. - page->mapping must be NULL. This fixes the panic reported by ZhangPeng. syzbot was able to loopback packets built with sendfile(), mapping pages owned by an ext4 file to TCP rx zerocopy. r3 = socket$inet_tcp(0x2, 0x1, 0x0) mmap(&(0x7f0000ff9000/0x4000)=nil, 0x4000, 0x0, 0x12, r3, 0x0) r4 = socket$inet_tcp(0x2, 0x1, 0x0) bind$inet(r4, &(0x7f0000000000)={0x2, 0x4e24, @multicast1}, 0x10) connect$inet(r4, &(0x7f00000006c0)={0x2, 0x4e24, @empty}, 0x10) r5 = openat$dir(0xffffffffffffff9c, &(0x7f00000000c0)='./file0\x00', 0x181e42, 0x0) fallocate(r5, 0x0, 0x0, 0x85b8) sendfile(r4, r5, 0x0, 0x8ba0) getsockopt$inet_tcp_TCP_ZEROCOPY_RECEIVE(r4, 0x6, 0x23, &(0x7f00000001c0)={&(0x7f0000ffb000/0x3000)=nil, 0x3000, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}, &(0x7f0000000440)=0x40) r6 = openat$dir(0xffffffffffffff9c, &(0x7f00000000c0)='./file0\x00', 0x181e42, 0x0)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.002 (13.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 14th percentile — 13.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000
Affected products
- Linux — versions 93ab6cc69162775201587cc9da00d5016dc890e2, 4.18, 0
- Linux Kernel — versions 6.8
- Debian Linux — versions 10.0
Public proof-of-concept exploits
References
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch, Mailing List)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch, Mailing List)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch, Mailing List)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch, Mailing List)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch, Mailing List)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch, Mailing List)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List)
Frequently asked questions
- What is CVE-2024-26640?
- CVE-2024-26640 is a high-severity vulnerability in Linux. CVSS score: 7.8/10. Published 2024-03-18.
- How severe is CVE-2024-26640?
- High severity. CVSS v3 base score is 7.8 out of 10.
- Is CVE-2024-26640 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.