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NVD / CVE Program· CNA GitHub_M

CVE-2025-49847: llama.cpp Vulnerable to Buffer Overflow via Malicious GGUF Model

Noroxi assessment

Priority: Monitor (action score 35/100)

  • 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: 0.51% (FIRST EPSS).
  • Anyone who can reach it over the internet 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: llama.cpp (Debian:14) 5713+dfsg-1; llamacpp (openSUSE:Tumbleweed) 5699-1.1.

Low priority for now. Upgrade to llama.cpp (Debian:14) 5713+dfsg-1; llamacpp (openSUSE:Tumbleweed) 5699-1.1 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

llama.cpp is an inference of several LLM models in C/C++. Prior to version b5662, an attacker‐supplied GGUF model vocabulary can trigger a buffer overflow in llama.cpp’s vocabulary‐loading code. Specifically, the helper _try_copy in llama.cpp/src/vocab.cpp: llama_vocab::impl::token_to_piece() casts a very large size_t token length into an int32_t, causing the length check (if (length < (int32_t)size)) to be bypassed. As a result, memcpy is still called with that oversized size, letting a malicious model overwrite memory beyond the intended buffer. This can lead to arbitrary memory corruption and potential code execution. This issue has been patched in version b5662.

HighCVSS 8.8 · v3.1—No exploit Fix available
Published
Jun 17, 2025
Updated
Jun 17, 2026
EPSS
0.5% · 44th percentile

Report tools

JSON

Action score

35

Monitor

Low priority for now.

CVSS
35 / 40 · 8.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.5%

CISA SSVC decision

Exploitation
proof of concept
Automatable
no
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · GitHub_M
8.8
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.

Follow CVE-2025-49847

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • 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.

VendorProduct
ggmlllama.cpp

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • ggml llama.cppbefore b5662

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.

  • ggml-org llama.cpp

    • < b5662affected

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:14llama.cppbefore 5713+dfsg-15713+dfsg-1
openSUSE:Tumbleweedllamacppbefore 5699-1.15699-1.1

Same product

ggml: all records

Other highest-scoring records for the same primary product.

  • CVE-2024-42479llama.cpp allows write-what-where in rpc_server::set_tensor
    40Plan
  • CVE-2026-34159llama.cpp: Unauthenticated RCE via GRAPH_COMPUTE buffer=0 bypass in llama.cpp RPC backend
    39Monitor
  • CVE-2026-21869llama.cpp has Out-of-bounds Write in llama-server
    39Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2024-42477Aug 12, 2024 · llama.cpp global-buffer-overflow in ggml_type_size
    30Monitor
  • ← EarlierCVE-2024-42478Aug 12, 2024 · llama.cpp allows Arbitrary Address Read in rpc_server::get_tensor
    39Monitor
  • Later →CVE-2025-52566Jun 24, 2025 · llama.cpp tokenizer signed vs. unsigned heap overflow
    35Monitor

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
debian:llama.cpp5713+dfsg-1 · Debian:14Package registry (OSV)
opensuse:llamacpp5699-1.1 · openSUSE:TumbleweedPackage 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.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

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

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

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

  • CVE-2026-34159288 days apartllama.cpp: Unauthenticated RCE via GRAPH_COMPUTE buffer=0 bypass in llama.cpp RPC backend
    39Monitor
  • CVE-2025-525667 days apartllama.cpp tokenizer signed vs. unsigned heap overflow
    35Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet 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
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
Required
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

CVSS vector

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

nvd-secondary

Change log

  1. Fix✗ → ✓

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References

Show all references (1 more)

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

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