CVE-2026-68278

CVE CVE-2026-68278EUVD EUVD-2026-55379Published 2026-08-10T12:01:54.000Z

What the advisory describes

In the Linux kernel, the following vulnerability has been resolved: drm/dp/mst: fix buffer overflows in sideband chunk accumulation drm_dp_sideband_append_payload() has three related bugs when processing device-provided sideband reply data: 1. Zero-length curchunk_len underflow: msg_len is a 6-bit field taken directly from the DP sideband header. If a device sends msg_len=0, curchunk_len is set to zero. The condition (curchunk_idx >= curchunk_len) is immediately true, and curchunk_len-1 wraps to 255 (u8 underflow). drm_dp_msg_data_crc4() reads 255 bytes from chunk[48], then memcpy() writes 255 bytes into msg[], both far out of bounds. 2. chunk[48] overflow: curchunk_len can reach 63 (6-bit field). chunk[] is only 48 bytes. Multi-iteration payload assembly appends 16-byte blocks until curchunk_idx reaches curchunk_len, writing up to 15 bytes past the end of chunk[] into msg[]. 3. msg[256] overflow: each chunk contributes (curchunk_len-1) bytes to msg[]. No check ensures curlen + (curchunk_len-1) stays within msg[256], so the memcpy can spill into adjacent struct fields. All three are reachable from any DP MST device that can forge sideband reply messages on a physical connection.

Source: EUVD (ENISA), in the words of the advisory.

Products the advisory names

These come from the advisory itself, not from any check we performed.

• Linux — Linux ad7f8a1f9ced7f049f9b66d588723f243a7034cd <ef0dbcc200c3389f1f781ab181932a97e54b51af; ad7f8a1f9ced7f049f9b66d588723f243a7034cd <53937a2787d29c7a460e984dc4f20ff6ac91dc65; ad7f8a1f9ced7f049f9b66d588723f243a7034cd <1e5827839ad0ceb0079d1560c321fa3656b54f21; ad7f8a1f9ced7f049f9b66d588723f243a7034cd <a6366b551079c79bf7bdbadd74c97358bcfe2d58; ad7f8a1f9ced7f049f9b66d588723f243a7034cd <55bd5e685bda455b9b50c835f8c8442d52a344a3; patch: 7.1.6; patch: 6.18.42; patch: 7.2-rc1; patch: 6.6.148; 3.17; patch: 6.12.101; patch: 0

The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.

Carried in the product catalogue

An estate covering these products can be recorded in Patchlage. An advisory about them appears in the next morning's situation report.

• Linux — Linux

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