CVE-2021-47353

udf: Fix NULL pointer dereference in udf_symlink function

MEDIUM
5.5
CVSS Score
Published: May 21, 2024 at 02:35 PM UTC
Updated: June 17, 2026 at 04:17 AM UTC
1 product affected across 1 vendorLinux Kernel

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Severity
MEDIUM5.5
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

Description

In the Linux kernel, the following vulnerability has been resolved: udf: Fix NULL pointer dereference in udf_symlink function In function udf_symlink, epos.bh is assigned with the value returned by udf_tgetblk. The function udf_tgetblk is defined in udf/misc.c and returns the value of sb_getblk function that could be NULL. Then, epos.bh is used without any check, causing a possible NULL pointer dereference when sb_getblk fails. This fix adds a check to validate the value of epos.bh.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 4.4.2762.6.12 ≤ v < 4.14.2402.6.12 ≤ v < 4.19.1982.6.12 ≤ v < 4.4.2762.6.12 ≤ v < 4.9.2762.6.12 ≤ v < 5.10.512.6.12 ≤ v < 5.12.182.6.12 ≤ v < 5.13.32.6.12 ≤ v < 5.142.6.12 ≤ v < 5.4.1334.10 ≤ v < 4.14.2404.15 ≤ v < 4.19.1984.20 ≤ v < 5.4.1334.5 ≤ v < 4.9.2765.11 ≤ v < 5.12.185.13 ≤ v < 5.13.35.5 ≤ v < 5.10.511da177e4c3f41524e886b7f1b8a0c1fc7321cac22.6.12
Vendor states this is fixed in 21bf1414580c36ffc8d8de043beb3508cf812238 (fixed)
Vendor states this is fixed in 2f3d9ddd32a28803baa547e6274983b67d5e287c (fixed)
Vendor states this is fixed in 3638705ecd5ad2785e996f820121c0ad15ce64b5 (fixed)
Vendor states this is fixed in 371566f63cbd0bb6fbb25b8fe9d5798268d35af9 (fixed)
Vendor states this is fixed in 5150877e4d99f85057a458daac7cd7c01005d5c6 (fixed)
Vendor states this is fixed in 80d505aee6398cf8beb72475c7edcf1733c1c68b (fixed)
Vendor states this is fixed in aebed6b19e51a34003d998da5ebb1dfdd2cb1d02 (fixed)
Vendor states this is fixed in baea588a42d675e35daeaddd10fbc9700550bc4d (fixed)
Vendor states this is fixed in fa236c2b2d4436d9f19ee4e5d5924e90ffd7bb43 (fixed)
Vendor states this is fixed in 2.6.12 (unaffected)
Vendor states this is fixed in 4.14.240 (unaffected)
Vendor states this is fixed in 4.19.198 (unaffected)
Vendor states this is fixed in 4.4.276 (unaffected)
Vendor states this is fixed in 4.9.276 (unaffected)
Vendor states this is fixed in 5.10.51 (unaffected)
Vendor states this is fixed in 5.12.18 (unaffected)
Vendor states this is fixed in 5.13.3 (unaffected)
Vendor states this is fixed in 5.14 (unaffected)
Vendor states this is fixed in 5.4.133 (unaffected)

References (9)

Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/21bf1414580c36ffc8d8de043beb3508cf812238
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/2f3d9ddd32a28803baa547e6274983b67d5e287c
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/3638705ecd5ad2785e996f820121c0ad15ce64b5
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/371566f63cbd0bb6fbb25b8fe9d5798268d35af9
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/5150877e4d99f85057a458daac7cd7c01005d5c6
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/80d505aee6398cf8beb72475c7edcf1733c1c68b
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/aebed6b19e51a34003d998da5ebb1dfdd2cb1d02
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/baea588a42d675e35daeaddd10fbc9700550bc4d

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
LOCAL
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-476

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