Linux Kernel af_alg Uninitialized Context via sock_kmalloc
CVE-2025-71113 Published on January 14, 2026
crypto: af_alg - zero initialize memory allocated via sock_kmalloc
In the Linux kernel, the following vulnerability has been resolved:
crypto: af_alg - zero initialize memory allocated via sock_kmalloc
Several crypto user API contexts and requests allocated with
sock_kmalloc() were left uninitialized, relying on callers to
set fields explicitly. This resulted in the use of uninitialized
data in certain error paths or when new fields are added in the
future.
The ACVP patches also contain two user-space interface files:
algif_kpp.c and algif_akcipher.c. These too rely on proper
initialization of their context structures.
A particular issue has been observed with the newly added
'inflight' variable introduced in af_alg_ctx by commit:
67b164a871af ("crypto: af_alg - Disallow multiple in-flight AIO requests")
Because the context is not memset to zero after allocation,
the inflight variable has contained garbage values. As a result,
af_alg_alloc_areq() has incorrectly returned -EBUSY randomly when
the garbage value was interpreted as true:
https://github.com/gregkh/linux/blame/master/crypto/af_alg.c#L1209
The check directly tests ctx->inflight without explicitly
comparing against true/false. Since inflight is only ever set to
true or false later, an uninitialized value has triggered
-EBUSY failures. Zero-initializing memory allocated with
sock_kmalloc() ensures inflight and other fields start in a known
state, removing random issues caused by uninitialized data.
Products Associated with CVE-2025-71113
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Affected Versions
Linux:- Version fe869cdb89c95d060c77eea20204d6c91f233b53 and below e125c8e346e4eb7b3e854c862fcb4392bc13ddba is affected.
- Version fe869cdb89c95d060c77eea20204d6c91f233b53 and below 543bf004e4eafbb302b1e6c78570d425d2ca13a0 is affected.
- Version fe869cdb89c95d060c77eea20204d6c91f233b53 and below f81244fd6b14fecfa93b66b6bb1d59f96554e550 is affected.
- Version fe869cdb89c95d060c77eea20204d6c91f233b53 and below 84238876e3b3b262cf62d5f4d1338e983fb27010 is affected.
- Version fe869cdb89c95d060c77eea20204d6c91f233b53 and below 5a4b65523608974a81edbe386f8a667a3e10c726 is affected.
- Version fe869cdb89c95d060c77eea20204d6c91f233b53 and below 51a5ab36084f3251ef87eda3e6a6236f6488925e is affected.
- Version fe869cdb89c95d060c77eea20204d6c91f233b53 and below 6f6e309328d53a10c0fe1f77dec2db73373179b6 is affected.
- Version 2.6.38 is affected.
- Before 2.6.38 is unaffected.
- Version 5.10.248, <= 5.10.* is unaffected.
- Version 5.15.198, <= 5.15.* is unaffected.
- Version 6.1.160, <= 6.1.* is unaffected.
- Version 6.6.120, <= 6.6.* is unaffected.
- Version 6.12.64, <= 6.12.* is unaffected.
- Version 6.18.3, <= 6.18.* is unaffected.
- Version 6.19, <= * is unaffected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.