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NVD / CVE Program· CNA GitHub_M

CVE-2025-53901: Wasmtime has host panic with `fd_renumber` WASIp1 function

Noroxi assessment

Priority: Monitor (action score 14/100)

  • 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: 0.38% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. A user must open a link or visit a page. No special conditions are required; it is repeatable.
  • Fixed version: wasmtime (crates.io) 24.0.4, 33.0.2, 34.0.2; wasmtime-wasi (crates.io) 33.0.2, 34.0.2, 24.0.4; rust-wasmtime (Debian:14) 36.0.5+dfsg-1.

Low priority for now. Upgrade to wasmtime (crates.io) 24.0.4, 33.0.2, 34.0.2; wasmtime-wasi (crates.io) 33.0.2, 34.0.2, 24.0.4; rust-wasmtime (Debian:14) 36.0.5+dfsg-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

Wasmtime is a runtime for WebAssembly. Prior to versions 24.0.4, 33.0.2, and 34.0.2, a bug in Wasmtime's implementation of the WASIp1 set of import functions can lead to a WebAssembly guest inducing a panic in the host (embedder). The specific bug is triggered by calling `path_open` after calling `fd_renumber` with either two equal argument values or a second argument being equal to a previously-closed file descriptor number value. The corrupt state introduced in `fd_renumber` will lead to the subsequent opening of a file descriptor to panic. This panic cannot introduce memory unsafety or allow WebAssembly to break outside of its sandbox, however. There is no possible heap corruption or memory unsafety from this panic. This bug is in the implementation of Wasmtime's `wasmtime-wasi` crate which provides an implementation of WASIp1. The bug requires a specially crafted call to `fd_renumber` in addition to the ability to open a subsequent file descriptor. Opening a second file descriptor is only possible when a preopened directory was provided to the guest, and this is common amongst embeddings. A panic in the host is considered a denial-of-service vector for WebAssembly embedders and is thus a security issue in Wasmtime. This bug does not affect WASIp2 and embedders using components. In accordance with Wasmtime's release process, patch releases are available as 24.0.4, 33.0.2, and 34.0.2. Users of other release of Wasmtime are recommended to move to a supported release of Wasmtime. Embedders who are using components or are not providing guest access to create more file descriptors (e.g. via a preopened filesystem directory) are not affected by this issue. Otherwise, there is no workaround at this time, and affected embeddings are recommended to update to a patched version which will not cause a panic in the host.

LowCVSS 3.5 · v3.1—No exploit Fix available
Published
Jul 18, 2025
Updated
Jun 17, 2026
EPSS
0.3% · 32th percentile

Report tools

JSON

Action score

14

Monitor

Low priority for now.

CVSS
14 / 40 · 3.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.3%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · GitHub_M
3.5
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

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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
bytecodealliancewasmtime

Affected versions

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

  • bytecodealliance wasmtimebefore 24.0.4
  • bytecodealliance wasmtime33.0.0 and later · before 33.0.2
  • bytecodealliance wasmtime34.0.0 and later · before 34.0.2

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.

  • bytecodealliance wasmtime

    • < 24.0.4, >= 33.0.0, < 33.0.2, >= 34.0.0, < 34.0.2affected

Package-level exposure

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

EcosystemPackageAffected rangeFix
crates.iowasmtimefrom 10.0.0 · before 24.0.424.0.4
crates.iowasmtimefrom 25.0.0 · before 33.0.233.0.2
crates.iowasmtimefrom 33.0.0 · before 33.0.233.0.2
crates.iowasmtimefrom 34.0.0 · before 34.0.234.0.2
crates.iowasmtime-wasifrom 25.0.0 · before 33.0.233.0.2
crates.iowasmtime-wasifrom 34.0.0 · before 34.0.234.0.2
crates.iowasmtime-wasibefore 24.0.424.0.4
Debian:13rust-wasmtimefrom 0—
Debian:14rust-wasmtimebefore 36.0.5+dfsg-136.0.5+dfsg-1
openSUSE:Tumbleweedkwctlbefore 1.27.1-1.11.27.1-1.1
openSUSE:Tumbleweedzellijbefore 0.43.1-2.10.43.1-2.1

Same product

bytecodealliance: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-115893Wasmtime: Cranelift backend on aarch64 can jump to incorrect target on large Wasm `br_table` instruction
    39Monitor
  • CVE-2026-115889Wasmtime: Bit-packing in Cranelift compiler causes silent overflow and miscompilation
    39Monitor
  • CVE-2022-39394wasmtime_trap_code C API function has out of bounds write vulnerability
    39Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2024-47813Oct 9, 2024 · Wasmtime race condition could lead to WebAssembly control-flow integrity and type safety violations
    11Monitor
  • ← EarlierCVE-2024-51745Nov 5, 2024 · Wasmtime doesn't fully sandbox all the Windows device filenames
    9Monitor
  • Later →CVE-2025-61670Oct 7, 2025 · Wasmtime has memory leak in C API with `externref` and `anyref` types
    4Monitor

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
crates.io:wasmtime24.0.4Package registry (OSV)
crates.io:wasmtime33.0.2Package registry (OSV)
crates.io:wasmtime34.0.2Package registry (OSV)
crates.io:wasmtime-wasi24.0.4Package registry (OSV)
crates.io:wasmtime-wasi33.0.2Package registry (OSV)
crates.io:wasmtime-wasi34.0.2Package registry (OSV)
debian:rust-wasmtime36.0.5+dfsg-1 · Debian:14Package registry (OSV)
opensuse:kwctl1.27.1-1.1 · openSUSE:TumbleweedPackage registry (OSV)
opensuse:zellij0.43.1-2.1 · 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.

No commit or PR link among the references.

Credits

All researchers

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.

No nightly-computed relations.

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.
  • A low-privileged account is enough.
  • A user must open a link or visit a page.
  • 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
Low
User interaction
Required
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
Low

Weakness class (CWE)

CWE-672 · Operation on a Resource after Expiration or Release

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/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.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (4 more)

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

All records