StableLib: Stack exhaustion denial of service via deeply nested CBOR arrays, maps, or tags

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

StableLib is a stable library of useful TypeScript and JavaScript code. Prior to 2.0.4, the @stablelib/cbor decoder recursively processes nested CBOR arrays, maps, and tags through _decodeValue() without enforcing a maximum nesting depth. A sufficiently deep structure exhausts the JavaScript call stack, causing a decoding exception and potentially terminating an uncaught request worker or process. This issue is fixed in version 2.0.4.

Source published

6 Oct 2026 19:44:03 UTC

Source modified

7 Oct 2026 14:40:22 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

StableLib is a stable library of useful TypeScript and JavaScript code. Prior to 2.0.4, the @stablelib/cbor decoder recursively processes nested CBOR arrays, maps, and tags through _decodeValue() without enforcing a maximum nesting depth. A sufficiently deep structure exhausts the JavaScript call stack, causing a decoding exception and potentially terminating an uncaught request worker or process. This issue is fixed in version 2.0.4.

Source published

Oct 6, 2026, 7:44:03 PM (timezone not stated)

Source modified

Oct 7, 2026, 2:40:22 PM (timezone not stated)

Observed here

11 Nov 2026 05:32:20 UTC

Source terms

ENISA EUVD · source terms and attribution apply

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EUVD CVSS 4.0 · 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

StableLib is a stable library of useful TypeScript and JavaScript code. Prior to 2.0.4, the @stablelib/cbor decoder recursively processes nested CBOR arrays, maps, and tags through _decodeValue() without enforcing a maximum nesting depth. A sufficiently deep structure exhausts the JavaScript call stack, causing a decoding exception and potentially terminating an uncaught request worker or process. This issue is fixed in version 2.0.4.

Source published

6 Oct 2026 20:17:26 UTC

Source modified

7 Oct 2026 15:17:12 UTC

Observed here

25 Oct 2026 04:17:41 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · [email protected] · Secondary · 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

### Summary `@stablelib/cbor` decodes nested CBOR structures recursively and does not enforce a maximum nesting depth. A sufficiently deep attacker-controlled CBOR payload can therefore crash decoding with `RangeError: Maximum call stack size exceeded`. ### Details The decoder processes arrays, maps, and tagged values through recursive calls. Each nested container causes another descent into `_decodeValue()` until a leaf value is reached. There is no depth limit, no iterative fallback, and no protection against pathological nesting. An attacker can therefore supply a payload made of thousands of nested arrays, maps, or tags and force the decoder to recurse until the JavaScript call stack is exhausted. ### PoC ```js import { decode } from "@stablelib/cbor"; const depth = 12000; const payload = new Uint8Array(depth + 1); // Build [[[...[null]...]]] payload.fill(0x81, 0, depth); // array(1) payload[depth] = 0xf6; // null decode(payload); // RangeError: Maximum call stack size exceeded ``` ### Impact Any application that decodes attacker-controlled CBOR can be forced into a reliable denial of service with a single crafted payload. The immediate result is an exception during decoding. In services that do not catch that exception safely, the request fails and the worker or process handling the decode may terminate. ### Solution Upgrade to version 2.0.4. The stack is limited to 128 by default, but can be configured using the `maxDepth` option. Catch the `CBORMaxDepthExceededError` exception.

Source published

4 Apr 2026 05:33:09 UTC

Source modified

7 Oct 2026 10:56:09 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V4 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Publisher rating · HIGH