Critical severity · published Aug 22, 2026
CVE-2026-74611
tls: rx: restore msg_iter before TLS 1.3 optimistic retry
9.8
CVSS
0.5%
EPSS
No
On KEV
Description
In the Linux kernel, the following vulnerability has been resolved: tls: rx: restore msg_iter before TLS 1.3 optimistic retry tls_decrypt_sg() advances msg->msg_iter when it maps user pages for the optimistic TLS 1.3 zero-copy path. If the decrypted record turns out not to be unpadded application data, tls_decrypt_sw() retries into a kernel skb, but leaves the iterator advanced. The subsequent copy from the skb then writes decrypted bytes again at a later point in the caller iovecs while recvmsg() reports only the post-retry length. A TLS peer can trigger this after the receiver enables TLS_RX_EXPECT_NO_PAD. Revert the iterator by the number of bytes consumed by the optimistic mapping before retrying without zero-copy. Add a selftest which sends a TLS 1.3 control record with TLS_RX_EXPECT_NO_PAD enabled and verifies that recvmsg() does not overwrite later iovecs beyond the returned length.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 39% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Linux · Linux
ce61327ce989b63c0bd1cc7afee00e218ee696ac before c71bacacd59166adbea423a04e7474b0e8245b84; ce61327ce989b63c0bd1cc7afee00e218ee696ac before 3c4e21b1bf8e666a1c141e0f5813ece929570deb; ce61327ce989b63c0bd1cc7afee00e218ee696ac before 68787940274ec89f41dc91b1a68ee1a16a90735f; ce61327ce989b63c0bd1cc7afee00e218ee696ac before 3c837266a734e2a22b24d2d567404a501d405835; ce61327ce989b63c0bd1cc7afee00e218ee696ac before 1c8629651cb54f7b51db8fc0b1a9944e4a4b0f5e; 6.0 · source: vendor