net/tls: fix use-after-free in -EBUSY error path of tls_do_encryption
In the Linux kernel, the following vulnerability has been resolved: net/tls: fix use-after-free in -EBUSY error path of tls_do_encryption The -EBUSY handling in tls_do_encryption(), introduced by commit 859054147318 ("net: tls: handle backlogging of crypto requests"), has a use-after-free due to double cleanup of encrypt_pending and the scatterlist entry. When crypto_aead_encrypt() returns -EBUSY, the request is enqueued to the cryptd backlog and the async callback tls_encrypt_done() will be invoked upon completion. That callback unconditionally restores the scatterlist entry (sge->offset, sge->length) and decrements ctx->encrypt_pending. However, if tls_encrypt_async_wait() returns an error, the synchronous error path in tls_do_encryption() performs the same cleanup again, double-decrementing encrypt_pending and double-restoring the scatterlist. The double-decrement corrupts the encrypt_pending sentinel (initialized to 1), making tls_encrypt_async_wait() permanently skip the wait for pending async callbacks. A subsequent sendmsg can then free the tls_rec via bpf_exec_tx_verdict() while a cryptd callback is still pending, resulting in a use-after-free when the callback fires on the freed record. Fix this by skipping the synchronous cleanup when the -EBUSY async wait returns an error, since the callback has already handled encrypt_pending and sge restoration.
CVE-2026-31533
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-31533
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "3ade391adc584f17b5570fd205de3ad029090368",
"lessThan": "414fc5e5a5aff776c150f1b86770e0a25a35df3a",
"versionType": "git"
},
{
"status": "affected",
"version": "cd1bbca03f3c1d845ce274c0d0a66de8e5929f72",
"lessThan": "02f3ecadb23558bbe068e6504118f1b712d4ece0",
"versionType": "git"
},
{
"status": "affected",
"version": "13eca403876bbea3716e82cdfe6f1e6febb38754",
"lessThan": "0e43e0a3c94044acc74b8e0927c27972eb5a59e8",
"versionType": "git"
},
{
"status": "affected",
"version": "8590541473188741055d27b955db0777569438e3",
"lessThan": "aa9facde6c5005205874c37db3fd25799d741baf",
"versionType": "git"
},
{
"status": "affected",
"version": "8590541473188741055d27b955db0777569438e3",
"lessThan": "5d70eb25b41e9b010828cd12818b06a0c3b04412",
"versionType": "git"
},
{
"status": "affected",
"version": "8590541473188741055d27b955db0777569438e3",
"lessThan": "2694d408b0e595024e0fc1d64ff9db0358580f74",
"versionType": "git"
},
{
"status": "affected",
"version": "8590541473188741055d27b955db0777569438e3",
"lessThan": "a9b8b18364fffce4c451e6f6fd218fa4ab646705",
"versionType": "git"
},
{
"status": "affected",
"version": "ab6397f072e5097f267abf5cb08a8004e6b17694",
"versionType": "git"
},
{
"status": "affected",
"version": "5.15.160",
"lessThan": "5.15.203",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.1.84",
"lessThan": "6.1.169",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.6.18",
"lessThan": "6.6.135",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.7.6",
"lessThan": "6.8",
"versionType": "semver"
}
],
"programFiles": [
"net/tls/tls_sw.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.8"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.8",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.15.203",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.169",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.135",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.82",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.23",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "6.19.13",
"versionType": "semver",
"lessThanOrEqual": "6.19.*"
},
{
"status": "unaffected",
"version": "7.0",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/tls/tls_sw.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-31533
Source reference:
/cveMetadata/cveId
Publisher severity
critical
Source reference: /containers/cna/metrics
- Event
- #39919 · Revision 1
- Added to Heist Feed
- Publisher date