In the Linux kernel, the following vulnerability has been resolved: crypto: nx - fix nx_crypto_ctx_exit argument nx_crypto_ctx_shash_exit calls… (CVE-2026-63805)
In the Linux kernel, the following vulnerability has been resolved: crypto: nx - fix nx_crypto_ctx_exit argument nx_crypto_ctx_shash_exit calls nx_crypto_ctx_exit with crypto_shash_ctx(...) but crypto_shash_ctx gives a nx_crypto_ctx *, not a crypto_tfm *. Fix the type in nx_crypto_ctx_exit and drop the bogus crypto_tfm_ctx call. This fixes the following oops: BUG: Unable to handle kernel data access at 0xc0403effffffffc8 Faulting instruction address: 0xc000000000396cb4 Oops: Kernel access of bad area, sig: 11 [#15] Call Trace: nx_crypto_ctx_shash_exit+0x24/0x60 crypto_shash_exit_tfm+0x28/0x40 crypto_destroy_tfm+0x98/0x140 crypto_exit_ahash_using_shash+0x20/0x40 crypto_destroy_tfm+0x98/0x140 hash_release+0x1c/0x30 alg_sock_destruct+0x38/0x60 __sk_destruct+0x48/0x2b0 af_alg_release+0x58/0xb0 __sock_release+0x68/0x150 sock_close+0x20/0x40 __fput+0x110/0x3a0 sys_close+0x48/0xa0 system_call_exception+0x140/0x2d0 system_call_common+0xf4/0x258 .. which came from hardlink(1) opportunistically using AF_ALG. The same problem exists with nx_crypto_ctx_skcipher_exit getting a context it wasn't expecting, but apparently nobody hit that for years.
AI Analysis
Technical Summary
The Linux kernel crypto nx module had a vulnerability where nx_crypto_ctx_shash_exit called nx_crypto_ctx_exit with a context pointer of the wrong type (nx_crypto_ctx * instead of crypto_tfm *). This type mismatch caused kernel oops due to invalid memory access, as demonstrated by a BUG message and call trace involving crypto_shash_exit_tfm and related functions. The patch fixes the argument type in nx_crypto_ctx_exit and removes an incorrect crypto_tfm_ctx call. A similar issue existed in nx_crypto_ctx_skcipher_exit but was not exploited in practice.
Potential Impact
This vulnerability could cause kernel crashes (oops) due to invalid memory access when certain cryptographic context exit functions are called. This may lead to denial of service on affected systems. There is no evidence of exploitation in the wild or further impact such as privilege escalation.
Mitigation Recommendations
A fix has been applied to the Linux kernel to correct the argument type in nx_crypto_ctx_exit and remove the invalid call. Users should update to a Linux kernel version that includes this fix. Patch status is not explicitly stated; check the vendor or Linux kernel advisories for the specific fixed versions and apply updates accordingly.
In the Linux kernel, the following vulnerability has been resolved: crypto: nx - fix nx_crypto_ctx_exit argument nx_crypto_ctx_shash_exit calls… (CVE-2026-63805)
Description
In the Linux kernel, the following vulnerability has been resolved: crypto: nx - fix nx_crypto_ctx_exit argument nx_crypto_ctx_shash_exit calls nx_crypto_ctx_exit with crypto_shash_ctx(...) but crypto_shash_ctx gives a nx_crypto_ctx *, not a crypto_tfm *. Fix the type in nx_crypto_ctx_exit and drop the bogus crypto_tfm_ctx call. This fixes the following oops: BUG: Unable to handle kernel data access at 0xc0403effffffffc8 Faulting instruction address: 0xc000000000396cb4 Oops: Kernel access of bad area, sig: 11 [#15] Call Trace: nx_crypto_ctx_shash_exit+0x24/0x60 crypto_shash_exit_tfm+0x28/0x40 crypto_destroy_tfm+0x98/0x140 crypto_exit_ahash_using_shash+0x20/0x40 crypto_destroy_tfm+0x98/0x140 hash_release+0x1c/0x30 alg_sock_destruct+0x38/0x60 __sk_destruct+0x48/0x2b0 af_alg_release+0x58/0xb0 __sock_release+0x68/0x150 sock_close+0x20/0x40 __fput+0x110/0x3a0 sys_close+0x48/0xa0 system_call_exception+0x140/0x2d0 system_call_common+0xf4/0x258 .. which came from hardlink(1) opportunistically using AF_ALG. The same problem exists with nx_crypto_ctx_skcipher_exit getting a context it wasn't expecting, but apparently nobody hit that for years.
CVSS v3.1
Score 7.8high
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Linux kernel crypto nx module had a vulnerability where nx_crypto_ctx_shash_exit called nx_crypto_ctx_exit with a context pointer of the wrong type (nx_crypto_ctx * instead of crypto_tfm *). This type mismatch caused kernel oops due to invalid memory access, as demonstrated by a BUG message and call trace involving crypto_shash_exit_tfm and related functions. The patch fixes the argument type in nx_crypto_ctx_exit and removes an incorrect crypto_tfm_ctx call. A similar issue existed in nx_crypto_ctx_skcipher_exit but was not exploited in practice.
Potential Impact
This vulnerability could cause kernel crashes (oops) due to invalid memory access when certain cryptographic context exit functions are called. This may lead to denial of service on affected systems. There is no evidence of exploitation in the wild or further impact such as privilege escalation.
Mitigation Recommendations
A fix has been applied to the Linux kernel to correct the argument type in nx_crypto_ctx_exit and remove the invalid call. Users should update to a Linux kernel version that includes this fix. Patch status is not explicitly stated; check the vendor or Linux kernel advisories for the specific fixed versions and apply updates accordingly.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-3m8h-qjhw-m7c5
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-63805"]
- Ecosystems
- []
- Database Specific Severity
- null
- Cvss Version
- 3.1
Threat ID: 6a5d27ad2a4a8d5989131c38
Added to database: 07/19/2026, 19:38:21 UTC
Last enriched: 07/19/2026, 20:22:00 UTC
Last updated: 09/03/2026, 10:52:10 UTC
Views: 58
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