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NVD / CVE Program· CNA GitHub_M

CVE-2026-62291: libheif: Heap out of bounds write in libheif uncompressed encoder when writing images with mismatched auxiliary alpha dimensions

MediumCVSS 5.3 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 21/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.18% (FIRST EPSS).
  • Someone with local access to the system can trigger it. No account or password is required. A user must open a link or visit a page. No special conditions are required; it is repeatable.
  • Fixed version: strukturag libheif 1.23.1.

Low priority for now. Upgrade to strukturag libheif 1.23.1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

libheif is a HEIF and AVIF file format decoder and encoder. In 1.23.0 and earlier, a crafted image sequence with a 2x2 primary plane and a 256x256 auxiliary alpha plane can cause attacker-controlled heap corruption during a normal decode and re-encode workflow. Track_Visual::decode_next_image_sample() calls transfer_channel_from_image_as() without checking that the auxiliary alpha dimensions match the main frame. The resulting inconsistent image reaches heif_track_decode_next_image() and then heif_context_encode_image(). In unc_encoder::encode(), unc_encoder_component_interleave::encode_tile() sizes its buffer with compute_tile_data_size_bytes() using the primary dimensions but copies each component using its actual plane dimensions. The oversized alpha plane is therefore copied beyond the allocation, causing an out-of-bounds write; the inverse size mismatch can also produce an out-of-bounds read. This issue is fixed in version 1.23.1.

Published
Aug 18, 2026
Updated
Oct 22, 2026
EPSS
0.1% · 8th percentile

Report tools

JSON

Action score

21

Monitor

Low priority for now.

CVSS
21 / 40 · 5.3 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

CISA SSVC decision

Exploitation
proof of concept
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · GitHub_M
5.3
NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

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When you'll hear from us

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  • when exploit code appears or is weaponized
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  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

—

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

  • strukturag libheif

    • < 1.23.1affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:14libheifbefore 1.23.1-11.23.1-1
openSUSE:Leap 16.0libheifbefore 1.23.1-160000.1.11.23.1-160000.1.1
openSUSE:Tumbleweedlibheifbefore 1.23.1-1.11.23.1-1.1
SUSE:Linux Enterprise Module for Desktop Applications 15 SP7libheifbefore 1.23.1-150700.3.18.11.23.1-150700.3.18.1
SUSE:Linux Enterprise Server 16.0libheifbefore 1.23.1-160000.1.11.23.1-160000.1.1

Same product

strukturag: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-84383libheif: Heap buffer overflow in `scale_nearest_neighbor()` via duplicate Alpha planes from nested `iden`/`auxl` items
    39Monitor
  • CVE-2026-62292libheif: Out-of-bounds read in uncompressed unci tile range slicing
    34Monitor
  • CVE-2026-120208libheif 1.18.0 before 1.23.3 Heap Buffer Overflow via unci Mixed-Interleave Decoder
    30Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2026-50142Aug 18, 2026 · libheif: unbounded heap allocation in HEIF sequence parser (stsz fixed-size mode missing bound check)
    30Monitor
  • ← EarlierCVE-2026-62289Aug 18, 2026 · libheif: Integer underflow in Fraction constructor via double clap transform application
    17Monitor
  • Later →CVE-2026-62377Aug 18, 2026 · libheif: Reachable assertion in HeifContext::get_track() aborts on a valid-but-empty HEIF sequence file (context.cc:2110)
    17Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
strukturag libheif1.23.1 · descriptionVendor (CNA)
debian:libheif1.23.1-1 · Debian:14Package registry (OSV)
opensuse:libheif1.23.1-1.1 · openSUSE:TumbleweedPackage registry (OSV)
suse:libheif1.23.1-160000.1.1 · SUSE:Linux Enterprise Server 16.0Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-622920 days apartlibheif: Out-of-bounds read in uncompressed unci tile range slicing
    34Monitor
  • CVE-2026-3288291 days apartlibheif: Heap Buffer OOB Read in overlay compositing due to wrong alpha stride
    28Monitor
  • CVE-2026-8445131 days apartlibheif: Incomplete fix for CVE-2026-62292 leaves libheif vulnerable to an out-of-bounds read
    26Monitor
  • CVE-2026-8444831 days apartlibheif: Heap out-of-bounds read in libheif inline-mask region API (heif_region_item_add_region_inline_mask_data / heif_region_get_mask_image)
    16Monitor
  • CVE-2026-8444931 days apartlibheif hOp_RGB24_32_to_YCbCr Memory Access Error / SEGV
    14Monitor

Not on record for this CVE: researcher credit · public bounty program.

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • No account or password is required.
  • A user must open a link or visit a page.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
low · data can be read
Integrity
low · data or configuration can be modified
Availability
low · the service can be disrupted
Attack vector
Local
Attack complexity
Low
Privileges required
None
User interaction
Required
Scope
Unchanged
Confidentiality impact
Low
Integrity impact
Low
Availability impact
Low

Weakness class (CWE)

CWE-125 · Out-of-bounds Read

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

ATT&CK techniques

—

References

Show all references (2 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records