CVE-2026-46344: liboqs: Heap-buffer-overflow in XMSS verification path via OID-controlled parameter mismatch (xmss_commons.c:194)
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: 0.30% (FIRST EPSS).
- Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
- According to CISA the attack is automatable: targets can be found by mass scanning.
- Fixed version: open-quantum-safe liboqs 0.16.0.
Low priority for now. Upgrade to open-quantum-safe liboqs 0.16.0 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
liboqs is a C-language cryptographic library that provides implementations of post-quantum cryptography algorithms. Prior to 0.16.0, an out-of-bounds read has been identified in the XMSS and XMSS^MT stateful signature verification code. When the verification function is called with a correctly-sized signature buffer for the declared algorithm but a public key whose OID bytes (pk[0..3]) reference a different XMSS parameter set with a larger sig_bytes, the implementation re-parses the OID from the public key inside xmss_sign_open / xmssmt_sign_open and uses the resulting (larger) sig_bytes to index the caller-supplied signature buffer. As with CVE-2026-44518, the out-of-bounds bytes are consumed only as input to an internal hash computation and are not returned to the caller, so no oracle exists to leak their contents to an attacker. The primary observable effect is a possible crash (denial of service) of the verifying process if the read crosses into an unmapped memory page. This vulnerability is fixed in 0.16.0.
- Published
- May 29, 2026
- Updated
- Jul 22, 2026
- EPSS
- 0.3% · 23th percentile
- CWE
- CWE-125
Report tools
Action score
21
Low priority for now.
- CVSS
- 21 / 40 · 5.3 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.3%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- 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.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
Is your version affected? Check itNoroxi 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.
We use this product, ask for helpAffected 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.
| Vendor | Product | CPE |
|---|---|---|
| openquantumsafe | liboqs | cpe:2.3:a:openquantumsafe:liboqs |
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.
open-quantum-safe liboqs
- < 0.16.0affected
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- openquantumsafe liboqsup to 0.15.0 inclusive
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| openSUSE:Leap 16.0 | liboqs | before 0.16.0-160000.1.1 | 0.16.0-160000.1.1 |
| openSUSE:Leap 16.0 | oqs-provider | before 0.11.0.32-160000.1.1 | 0.11.0.32-160000.1.1 |
| openSUSE:Tumbleweed | liboqs | before 0.16.0-2.1 | 0.16.0-2.1 |
| SUSE:Linux Enterprise Module for Basesystem 15 SP7 | liboqs | before 0.16.0-150600.3.6.1 | 0.16.0-150600.3.6.1 |
| SUSE:Linux Enterprise Module for Basesystem 15 SP7 | oqs-provider | before 0.11.0.32-150600.3.9.1 | 0.11.0.32-150600.3.9.1 |
| SUSE:Linux Enterprise Server 16.0 | liboqs | before 0.16.0-160000.1.1 | 0.16.0-160000.1.1 |
| SUSE:Linux Enterprise Server 16.0 | oqs-provider | before 0.11.0.32-160000.1.1 | 0.11.0.32-160000.1.1 |
Same product
openquantumsafe: all recordsOther highest-scoring records for the same primary product.
- CVE-2024-31510An issue in Open Quantum Safe liboqs v.10.0 allows a remote attacker to escalate privileges via the crypto_sign_signature parameter in the…39Monitor
- CVE-2024-54137liboqs has a correctness error in HQC decapsulation30Monitor
- CVE-2024-36405Control-flow timing leak in Kyber reference implementation when compiled with Clang 15-18 for -Os, -O1 and other options30Monitor
Published before and after this one in the same product
- ← EarlierCVE-2025-48946May 30, 2025 · liboqs affected by theoretical design flaw in HQC14Monitor
- ← EarlierCVE-2025-52473Jul 10, 2025 · liboqs secret-dependent branching in HQC reference implementation when compiled with Clang 17-2022Monitor
- ← EarlierCVE-2026-44518May 29, 2026 · liboqs: XMSS Buffer Overread Bug21Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| open-quantum-safe liboqs | 0.16.0 · description | Vendor (CNA) |
| opensuse:liboqs | 0.16.0-2.1 · openSUSE:Tumbleweed | Package registry (OSV) |
| opensuse:oqs-provider | 0.11.0.32-160000.1.1 · openSUSE:Leap 16.0 | Package registry (OSV) |
| suse:liboqs | 0.16.0-160000.1.1 · SUSE:Linux Enterprise Server 16.0 | Package registry (OSV) |
| suse:oqs-provider | 0.11.0.32-160000.1.1 · SUSE:Linux Enterprise Server 16.0 | Package 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.
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Not on record for this CVE: EPSS history · researcher credit · variant or chain candidate · public bounty program.
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- low · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- Low
Weakness class (CWE)
CWE-125 · Out-of-bounds ReadCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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.
Attack patterns (CAPEC)
ATT&CK techniques
—
Change log (1)
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (1 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.