CVE-2026-46303 | isofs: validate Rock Ridge CE continuation extent against volume size

In the Linux kernel, the following vulnerability has been resolved: isofs: validate Rock Ridge CE continuation extent against volume size rock_continue() reads rs->cont_extent verbatim from the Rock Ridge CE record and passes it to sb_bread() without checking that the block number is within the mounted ISO 9660 volume. commit e595447e177b ("[PATCH] rock.c: handle corrupted directories") added cont_offset and cont_size rejection for the CE continuation but did not validate the extent block number itself. commit f54e18f1b831 ("isofs: Fix infinite looping over CE entries") later capped the CE chain length at RR_MAX_CE_ENTRIES = 32 but again left the block number unchecked. With a crafted ISO mounted via udisks2 (desktop optical auto-mount) or via CAP_SYS_ADMIN mount, rs->cont_extent can therefore point at an out-of-range block or at blocks belonging to an adjacent filesystem on the same block device. sb_bread() on an out-of-range block returns NULL cleanly via the block layer EIO path, so there is no memory-safety violation. For in-range reads of adjacent- filesystem data, the CE buffer is parsed as Rock Ridge records and only the text of SL sub-records reaches userspace through readlink(), which makes the info-leak channel narrow and difficult to exploit; still, rejecting the malformed CE outright matches the rejection shape already present in the same function for cont_offset and cont_size. Add an ISOFS_SB(sb)->s_nzones bounds check to rock_continue() next to the existing offset/size rejection, printing the same corrupted-directory-entry notice.

Published: 2026-06-08 Last update: 2026-06-17 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD Status：Received，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-46303 is rated Low Risk (39.8/100): CVSS High severity, with low exploitation likelihood (EPSS 0.28%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-46303

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.02% 0.28% +0.25%
2 2026-06-09 — 0.02% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-46303

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.2 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 4.2 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Weakness enumeration for CVE-2026-46303

GitHub Security Advisory for CVE-2026-46303

GHSA-phcq-c45r-9f84 · Severity: high — In the Linux kernel, the following vulnerability has been resolved: isofs: validate Rock Ridge...

OS Trackers for CVE-2026-46303

vendor priority summary link
debian not yet assigned CVE-2026-46303 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 3, open 2. https://security-tracker.debian.org/tracker/CVE-2026-46303
suse low — https://www.suse.com/security/cve/CVE-2026-46303/
ubuntu medium CVE-2026-46303 medium priority: Ubuntu including 161 source packages (linux, linux-allwinner-5.19, …), 1449 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): DNE 1045, ignored 176, needed 127, released 87, pending 14. https://ubuntu.com/security/CVE-2026-46303

Affected software / configurations for CVE-2026-46303

Vendor Product Version Raw CPE
linux linux_kernel >= 3.19, < 5.10.258 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 3.19, < 5.15.209 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 3.19, < 6.1.175 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 3.19, < 6.6.140 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 3.19, < 6.12.88 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 3.19, < 6.18.30 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 3.19, < 7.0.7 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 3.19, < 7.1 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 2.6.32.66 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 3.2.67 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 3.4.107 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 3.10.64 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 3.12.36 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 3.14.28 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 3.17.8 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 3.18.2 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

References for CVE-2026-46303

cvelogic Threat Intelligence