Out-of-Bounds Read in go.opentelemetry.io/obi (CVE-2026-45681)
Summary
Vulnerability in go.opentelemetry.io/obi (CVE-2026-45681). Confidential information can be exposed externally. Exploitable via k_kprobes_http2_buf_size. Mitigation: upgrade to 0.9.0 or later.
Original description
The description as published by the source.
Summary
The per-CPU message-buffer fallback path uses a 256-byte backup buffer but preserves the original payload size, which can be up to 8KB. If a CPU mismatch occurs, OBI can read beyond the fallback buffer and leak adjacent memory into telemetry.
Details
k_kprobes_http2_buf_size is defined as 256 bytes, the size of the fallback buffer.
Introduces 8KB per-CPU buffer and 256-byte fallback_buf in msg_buffer_t, creating a size mismatch for fallback use.
On CPU mismatch, fallback_buf is used but size is still set to m_buf->real_size (up to 8KB) and passed downstream.
bytes_len (from m_buf->real_size) is used to read payload data from u_buf; if u_buf is the 256B fallback, this can over-read and leak memory into telemetry.
Source: GitHub Security Advisories (Global) 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-2026-45681 has been found in go.opentelemetry.io/obi.
Attackers can target a specific entry point like k_kprobes_http2_buf_size over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 5.9/10.
What to do: upgrade go.opentelemetry.io/obi to 0.9.0 or later.
If unsure, ask your IT team or search "go.opentelemetry.io/obi CVE-2026-45681" on the vendor's site.
CVE-2026-45681 (go.opentelemetry.io/obi) — CWE-125 / CVSS v3 5.9
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: k_kprobes_http2_buf_size / fallback_buf / msg_buffer_t / u_buf
Patched: 0.9.0 — 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.
Out-of-bounds read (CWE-125) exists in go.opentelemetry.io/obi. Attackers reach the vulnerable code path via k_kprobes_http2_buf_size without authentication.
Check the vendor advisory for the affected versions of go.opentelemetry.io/obi. Attack surface: k_kprobes_http2_buf_size / fallback_buf / msg_buffer_t / u_buf.
Severity: Medium (CVSS 5.9/10). Confidential information can be exposed externally.
Update to 0.9.0.
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 'go.opentelemetry.io/obi' . 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 'go.opentelemetry.io/obi' . | 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
go.opentelemetry.io/obi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 go.opentelemetry.io/obi to 0.9.0ステージング環境で 0.9.0 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 nvd.nist.gov
- package github.com
- web github.com
- web github.com
- web github.com