Vulnerability in PeterO.Cbor (CVE-2024-21909)
Summary
Vulnerability in PeterO.Cbor (CVE-2024-21909). Risk of unauthorized operations or information disclosure. Exploitable via DecodeFromBytes. Mitigation: upgrade to 4.5.1 or later.
Original description
The description as published by the source.
Impact
Due to this library's use of an inefficient algorithm, it is vulnerable to a denial of service attack when a maliciously crafted input is passed to DecodeFromBytes or other CBOR decoding mechanisms in this library.
Affected versions include versions 4.0.0 through 4.5.0.
This vulnerability was privately reported to me.
Patches
This issue has been fixed in version 4.5.1. Users should use the latest version of this library. (The latest version is not necessarily 4.5.1. Check the NuGet page to see the latest version's version number.)
Workarounds
Again, users should use the latest version of this library.
In the meantime, note that the inputs affected by this issue are all CBOR maps or contain CBOR maps. An input that decodes to a single CBOR object is not capable of containing a CBOR map if—
- it begins with a byte other than 0x80 through 0xDF, or
- it does not contain a byte in the range 0xa0 through 0xBF.
Such an input is not affected by this vulnerability and an application can choose to perform this check before passing it to a CBOR decoding mechanism.
For more information
If you have any questions or comments about this advisory:
- Open an issue in the CBOR repository.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2024-21909 has been found in PeterO.Cbor.
Attackers can target a specific entry point like DecodeFromBytes over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 7.5/10.
What to do: upgrade PeterO.Cbor to 4.5.1 or later.
If unsure, ask your IT team or search "PeterO.Cbor CVE-2024-21909" on the vendor's site.
CVE-2024-21909 (PeterO.Cbor) — CWE-407 / CVSS v3 7.5
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: DecodeFromBytes
Patched: 4.5.1 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-407) exists in PeterO.Cbor. Attackers reach the vulnerable code path via DecodeFromBytes without authentication.
Check the vendor advisory for the affected versions of PeterO.Cbor. Attack surface: DecodeFromBytes.
Severity: High (CVSS 7.5/10). Risk of unauthorized operations or information disclosure.
Update to 4.5.1.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'PeterO.Cbor' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'PeterO.Cbor' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
PeterO.Cborを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade PeterO.Cbor to 4.5.1ステージング環境で 4.5.1 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory github.com
- advisory vulncheck.com
- package github.com
- web github.com
- web github.com
- web github.com