Wasmtime is a standalone JIT-style runtime for WebAssembly, using Cranelift. There is a use after free vulnerability in Wasmtime when both running Wasm that uses externrefs and enabling epoch interruption in Wasmtime. If you are not explicitly enabling epoch interruption (it is disabled by default) then you are not affected. If you are explicitly disabling the Wasm reference types proposal (it is enabled by default) then you are also not affected. The use after free is caused by Cranelift failing to emit stack maps when there are safepoints inside cold blocks. Cold blocks occur when epoch interruption is enabled. Cold blocks are emitted at the end of compiled functions, and change the order blocks are emitted versus defined. This reordering accidentally caused Cranelift to skip emitting some stack maps because it expected to emit the stack maps in block definition order, rather than block emission order. When Wasmtime would eventually collect garbage, it would fail to find live references on the stack because of the missing stack maps, think that they were unreferenced garbage, and therefore reclaim them. Then after the collection ended, the Wasm code could use the reclaimed-too-early references, which is a use after free. Patches have been released in versions 0.34.2 and 0.35.2, which fix the vulnerability. All Wasmtime users are recommended to upgrade to these patched versions. If upgrading is not an option for you at this time, you can avoid the vulnerability by either: disabling the Wasm reference types proposal, config.wasm_reference_types(false); or by disabling epoch interruption if you were previously enabling it. config.epoch_interruption(false).
CVE-2022-24791
“—” beside the score: it is equal to NVD's CVSS score.
This high-severity CVE scores 8.1 under NVD CVSS v3. EPSS exploit probability: 1.2% (67th percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.
- High severity, but no confirmed exploitation yet
A fix is available — apply it.
- CVSS v3
- 8.1
- EG Score
- 8.1HIGHmedium confidence
- EG Risk
- 37EG Risk 37/100
EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.
How it’s computed (value × EchelonGraph’s weight)Severity81% × 45%Impact severity (EG Severity): CVSS 8.1 of 10. Never the KEV-floored or EPSS-lifted EG Score.Exploitation1.2% × 40%FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.Automatability0% × 15%CISA's SSVC Automatable value: no (Vulnrichment).SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Track* at high (mission-essential systems).Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.Action: A fix is available. Apply it within your standard update timelines. - EPSS PROB
- 1.2%
- EPSS %ILE
- 67th
- KEV
- Not listed
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (8.1): severity, escalated by confirmed exploitation. This CVE's 8.1 is its impact severity (EG Severity), not escalated.
- EG Severity
- 8.1 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.NVD CVSS v3 · CVSS v3.0 or v3.1
- EG Likelihood
- 1.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-20). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at low or medium mission impact; Track* at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).
A fix is available. Apply it within your standard update timelines.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it
Published
March 31, 2022
Last Modified
November 21, 2024
Advisory Details (2)
Auto-updated Sep 12, 2026Use after free with `externref`s and epoch interruption in Wasmtime · Advisory · bytecodealliance/wasmtime · GitHub
https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-gwc9-348x-qwv2commit 666c2554ea0e (bytecodealliance/wasmtime)
Fix landed in bytecodealliance/wasmtime commit 666c2554ea0e — awaiting tagged release
https://github.com/bytecodealliance/wasmtime/commit/666c2554ea0e1728c35aa41178cf235920db888aVendor Advisories for CVE-2022-24791(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Affected Packages
(1 across 1 ecosystem)
crates.io(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| wasmtime | — |
| — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 10× in last 7d / 33× in last 30d)
Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.
Showing the most recent 95 of 179 refreshes on record for this CVE.
A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. 5 repeat rows among the latest 100 are merged into the row they repeat. The 84 oldest rows on record are not shown and were not checked, so the counts can still include repeats.
- 2026-10-22 16:30 UTCEPSS rescoreEPSS 1.2% · 67th percentile
- 2026-10-21 16:28 UTCEPSS rescoreEPSS 1.2% · 67th percentile
- 2026-10-21 07:49 UTCEG score recompute
- 2026-10-20 16:29 UTCEPSS rescoreEPSS 1.2% · 67th percentile
- 2026-10-19 16:28 UTCEPSS rescoreEPSS 1.2% · 67th percentile
- 2026-10-18 16:28 UTCEPSS rescoreEPSS 1.2% · 67th percentile
- 2026-10-18 08:41 UTCEG score recompute
- 2026-10-17 16:29 UTCEPSS rescoreEPSS 1.2% · 67th percentile
- 2026-10-16 23:54 UTCOSV refresh
- 2026-10-16 16:34 UTCEPSS rescoreEPSS 1.2% · 67th percentile
- 2026-10-15 16:28 UTCEPSS rescoreEPSS 1.2% · 67th percentile
- 2026-10-14 16:29 UTCEPSS rescoreEPSS 1.2% · 67th percentile
- 2026-10-13 16:29 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-10-12 18:58 UTCEG score recompute
- 2026-10-12 16:30 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-10-11 23:24 UTCEG score recompute
- 2026-10-11 13:44 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-10-10 19:56 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-10-09 20:04 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-10-08 16:40 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-10-07 23:45 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-10-06 15:14 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-10-05 17:40 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-10-04 23:19 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-10-03 14:22 UTCEPSS rescoreEPSS 1.2% · 66th percentile
Show 70 moreShow fewer
- 2026-09-30 15:51 UTCEG score recompute
- 2026-09-30 15:00 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-09-29 15:15 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-09-28 13:48 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-09-27 13:41 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-09-26 00:22 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-09-25 02:24 UTCOSV refresh
- 2026-09-24 14:00 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-09-23 13:45 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-09-20 20:13 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-09-17 19:23 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-09-16 14:05 UTCEPSS rescoreEPSS 1.2% · 66th percentile
- 2026-09-15 03:06 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-09-13 16:43 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-09-12 14:57 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-09-11 14:49 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-09-11 09:33 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-09-08 21:57 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-09-07 15:58 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-09-06 13:45 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-09-05 17:55 UTCOSV refresh
- 2026-09-05 15:25 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-09-04 13:57 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-09-04 05:04 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-09-02 14:09 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-09-01 13:51 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-08-30 19:14 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-08-30 01:19 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-08-28 21:38 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-08-27 14:22 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-08-26 14:43 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-08-25 13:46 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-08-24 14:13 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-08-21 23:46 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-08-20 22:52 UTCEPSS rescoreEPSS 1.2% · 65th percentile
- 2026-08-19 17:01 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-08-19 04:32 UTCOSV refresh
- 2026-08-18 13:45 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-08-17 13:44 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-08-16 14:53 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-08-16 02:11 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-08-15 01:27 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-08-13 21:57 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-08-12 13:48 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-08-09 13:44 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-08-08 16:34 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-08-07 16:24 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-08-06 13:44 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-08-05 19:15 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-08-04 10:34 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-08-04 00:27 UTCOSV refresh
- 2026-08-03 10:33 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-08-02 02:24 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-08-01 04:13 UTCEPSS rescoreEPSS 1.2% · 64th percentile
- 2026-07-30 16:25 UTCEPSS rescoreEPSS 1.2% · 63rd percentile
- 2026-07-30 01:28 UTCEPSS rescoreEPSS 1.1% · 63rd percentile
- 2026-07-28 15:33 UTCEPSS rescoreEPSS 1.1% · 63rd percentile
- 2026-07-25 14:15 UTCEPSS rescoreEPSS 1.1% · 63rd percentile
- 2026-07-24 14:15 UTCEPSS rescoreEPSS 1.1% · 63rd percentile
- 2026-07-23 14:16 UTCEPSS rescoreEPSS 1.1% · 63rd percentile
- 2026-07-23 02:09 UTCEG score recompute
- 2026-07-22 22:56 UTCEG score recompute
- 2026-07-22 14:06 UTCEPSS rescoreEPSS 1.1% · 63rd percentile
- 2026-07-21 15:22 UTCEPSS rescoreEPSS 1.1% · 62nd percentile
- 2026-07-20 17:05 UTCEPSS rescoreEPSS 1.1% · 62nd percentile
- 2026-07-19 14:29 UTCEPSS rescoreEPSS 1.1% · 62nd percentile
- 2026-07-19 02:27 UTCEPSS rescoreEPSS 1.1% · 62nd percentile
- 2026-07-18 10:02 UTCEPSS rescoreEPSS 1.1% · 62nd percentile
- 2026-07-17 18:59 UTCOSV refresh
- 2026-07-16 17:00 UTCEPSS rescoreEPSS 1.1% · 62nd percentile
Related CVEs(same product + same CWE)
Same product
10 showncrates.io:wasmtime
Frequently asked(5)
What is CVE-2022-24791?
When was the CVE record for CVE-2022-24791 published?
Is CVE-2022-24791 actively exploited?
What is the CVSS score of CVE-2022-24791?
How do I remediate CVE-2022-24791?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2022-24791
Is Your Infrastructure Affected by CVE-2022-24791?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.