Answer in brief
CVE-2026-53003 records a High severity (CVSS 7.5) vulnerability in pppoe: drop PFC frames. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=7fb1b8ca8fa1ee34ffc328f17f78da68c7cc04e6 <cb3beef35ab5e0c1afca9fd7648c6ae499786377 || >=7fb1b8ca8fa1ee34ffc328f17f78da68c7cc04e6 <ba758fdf1399f310b30098b6faa3fd043de47dd2 || >=7fb1b8ca8fa1ee34ffc328f17f78da68c7cc04e6 <fcca1df05322bb04e344dd1178b54b76a08eb7c3 || >=7fb1b8ca8fa1ee34ffc328f17f78da68c7cc04e6 <8a5e840babc5c0fbd10c73728a13192347771ec6 || >=7fb1b8ca8fa1ee34ffc328f17f78da68c7cc04e6 <49e41b60ccd1bdbe9e218420f716dd5f9a2f9c71 || >=7fb1b8ca8fa1ee34ffc328f17f78da68c7cc04e6 <0cab5d077dd1efd2bd1a47271acc35894f945b4f || >=7fb1b8ca8fa1ee34ffc328f17f78da68c7cc04e6 <2b5c3c040d020e3ab3b9a8887031202d96843b1e || >=7fb1b8ca8fa1ee34ffc328f17f78da68c7cc04e6 <cc1ff87bce1ccd38410ab10960f576dcd17db679 | cb3beef35ab5e0c1afca9fd7648c6ae499786377, ba758fdf1399f310b30098b6faa3fd043de47dd2, fcca1df05322bb04e344dd1178b54b76a08eb7c3, 8a5e840babc5c0fbd10c73728a13192347771ec6, 49e41b60ccd1bdbe9e218420f716dd5f9a2f9c71, 0cab5d077dd1efd2bd1a47271acc35894f945b4f, 2b5c3c040d020e3ab3b9a8887031202d96843b1e, cc1ff87bce1ccd38410ab10960f576dcd17db679 |
| Linux/Linuxgeneric | 5.0 | Not reported |
Published upstream
Jun 24, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 24, 2026
In the Linux kernel, the following vulnerability has been resolved: pppoe: drop PFC frames RFC 2516 Section 7 states that Protocol Field Compression (PFC) is NOT RECOMMENDED for PPPoE. In practice, pppd does not support negotiating PFC for PPPoE sessions, and the current PPPoE driver assumes an uncompressed (2-byte) protocol field. However, the generic PPP layer function ppp_input() is not aware of the negotiation result, and still accepts PFC frames. If a peer with a broken implementation or an attacker sends a frame with a compressed (1-byte) protocol field, the subsequent PPP payload is shifted by one byte. This causes the network header to be 4-byte misaligned, which may trigger unaligned access exceptions on some architectures. To reduce the attack surface, drop PPPoE PFC frames. Introduce ppp_skb_is_compressed_proto() helper function to be used in both ppp_generic.c and pppoe.c to avoid open-coding.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2026-53003 records a High severity (CVSS 7.5) vulnerability in pppoe: drop PFC frames. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=7fb1b8ca8fa1ee34ffc328f17f78da68c7cc04e6 <cb3beef35ab5e0c1afca9fd7648c6ae499786377 || >=7fb1b8ca8fa1ee34ffc328f17f78da68c7cc04e6 <ba758fdf1399f310b30098b6faa3fd043de47dd2 || >=7fb1b8ca8fa1ee34ffc328f17f78da68c7cc04e6 <fcca1df05322bb04e344dd1178b54b76a08eb7c3 || >=7fb1b8ca8fa1ee34ffc328f17f78da68c7cc04e6 <8a5e840babc5c0fbd10c73728a13192347771ec6 || >=7fb1b8ca8fa1ee34ffc328f17f78da68c7cc04e6 <49e41b60ccd1bdbe9e218420f716dd5f9a2f9c71 || >=7fb1b8ca8fa1ee34ffc328f17f78da68c7cc04e6 <0cab5d077dd1efd2bd1a47271acc35894f945b4f || >=7fb1b8ca8fa1ee34ffc328f17f78da68c7cc04e6 <2b5c3c040d020e3ab3b9a8887031202d96843b1e || >=7fb1b8ca8fa1ee34ffc328f17f78da68c7cc04e6 <cc1ff87bce1ccd38410ab10960f576dcd17db679 | cb3beef35ab5e0c1afca9fd7648c6ae499786377, ba758fdf1399f310b30098b6faa3fd043de47dd2, fcca1df05322bb04e344dd1178b54b76a08eb7c3, 8a5e840babc5c0fbd10c73728a13192347771ec6, 49e41b60ccd1bdbe9e218420f716dd5f9a2f9c71, 0cab5d077dd1efd2bd1a47271acc35894f945b4f, 2b5c3c040d020e3ab3b9a8887031202d96843b1e, cc1ff87bce1ccd38410ab10960f576dcd17db679 |
| Linux/Linuxgeneric | 5.0 | Not reported |
Published upstream
Jun 24, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 24, 2026
In the Linux kernel, the following vulnerability has been resolved: pppoe: drop PFC frames RFC 2516 Section 7 states that Protocol Field Compression (PFC) is NOT RECOMMENDED for PPPoE. In practice, pppd does not support negotiating PFC for PPPoE sessions, and the current PPPoE driver assumes an uncompressed (2-byte) protocol field. However, the generic PPP layer function ppp_input() is not aware of the negotiation result, and still accepts PFC frames. If a peer with a broken implementation or an attacker sends a frame with a compressed (1-byte) protocol field, the subsequent PPP payload is shifted by one byte. This causes the network header to be 4-byte misaligned, which may trigger unaligned access exceptions on some architectures. To reduce the attack surface, drop PPPoE PFC frames. Introduce ppp_skb_is_compressed_proto() helper function to be used in both ppp_generic.c and pppoe.c to avoid open-coding.
Quoted source text, attributed separately from HOL analysis.