CVE-2020-15069
CVE-2020-15069 is a security flaw in Sophos XG Firewall. Attackers can run their own code on Sophos XG Firewall. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 6 Feb 2025.[1]
Sophos XG Firewall is business software or equipment. Most families won’t have it, but attackers break into it to get inside companies, and from there to what those companies hold about their customers, patients and staff. Sophos has published a fix or advice.
Description
CISA calls it a buffer overflow in Sophos XG Firewall. In its words: “Sophos XG Firewall contains a buffer overflow vulnerability that allows for remote code execution via the "HTTP/S bookmark" feature.”[1]
The CVE record adds: “Sophos XG Firewall 17.x through v17.5 MR12 allows a Buffer Overflow and remote code execution via the HTTP/S Bookmarks feature for clientless access. Hotfix HF062020.1 was published for all firewalls running v17.x.”[2]
The underlying weakness is buffer overflow (CWE-120), in MITRE’s list of common software weaknesses.
It scores 9.8 out of 10 on the Common Vulnerability Scoring System, which rates it critical, scored by NVD using CVSS 3.1.[2]
Affected versions
NVD’s record doesn’t list version ranges for it; Sophos’s advisory has them[3]. CISA names the product as Sophos XG Firewall.
Most families won’t have Sophos XG Firewall; it’s for whoever looks after IT at work.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 6 Feb 2025, 1,683 days after it was made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 27 Feb 2025 to fix it.[1]
FIRST’s Exploit Prediction Scoring System, which estimates how likely a flaw is to be used in attacks in the next 30 days from what it sees across the internet, puts it at 11%. That’s in the top 5% of the flaws it scores.[4]
CISA assesses it as automatable: attackers can run it against many targets at once.
CISA doesn’t say who was attacked, or how.
Fix
Sophos has published a fix or advice.[3] CISA’s required action: “Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.”[1]
- Check whether you use it.Sophos XG Firewall is business software or equipment, so most families won’t have it. If you run a business, or work from home on company equipment, ask whoever looks after your IT.
- Send this page to your IT person.Ask them to confirm it’s fixed, or not in use. CISA gave US government agencies until 27 Feb 2025 to fix it.
- If it can’t be fixed, take it offline.CISA’s advice when there’s no fix is to stop using the product, or take it off the internet, until there is one.
You can’t fix someone else’s server, but you can watch for what follows a break-in like this: a breach notice, a password reset you didn’t ask for, or a scam message that knows things it shouldn’t. HARD watches for those for you and your family.
Timeline
| Date | Event |
|---|---|
| The flaw is made public in the National Vulnerability Database, with a severity score of 9.8.[2] | |
| CISA adds it to its catalog of flaws known to be used in attacks.[1] | |
| CISA’s deadline for US government agencies to fix it.[1] | |
| FIRST puts the odds of it being used in attacks in the next 30 days at 11%.[4] |
See also
Other Sophos flaws
- CVE-2020-29574, Sophos CyberoamOS: (CROS) SQL injection ·
- CVE-2023-1671, Sophos Web Appliance: command injection ·
- CVE-2022-3236, Sophos Firewall: code injection ·
- CVE-2022-1040, Sophos Firewall: authentication bypass ·
- CVE-2020-25223, Sophos SG UTM: remote code execution ·
Other buffer overflow flaws
- CVE-2025-43520, Apple devices: classic buffer overflow ·
- CVE-2022-37055, D-Link Routers: buffer overflow ·
- CVE-2025-20333, Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense: secure firewall adaptive security appliance (ASA) and secure firewall threat defense (FTD) buffer overflow ·
- CVE-2023-41064, Apple iOS, iPadOS, and macOS: imageIO buffer overflow ·
- CVE-2023-33010, Zyxel Multiple Firewalls: buffer overflow ·
Added the same day
- CVE-2025-0411, 7-Zip: mark of the web bypass ·
- CVE-2024-21413, Microsoft Office Outlook: outlook improper input validation ·
- CVE-2022-23748, Audinate Dante Discovery: process control ·
- CVE-2020-29574, Sophos CyberoamOS: (CROS) SQL injection ·
Every Sophos flaw on CISA’s list · Everything added in February 2025
References
- ^ Cybersecurity and Infrastructure Security Agency. “Sophos XG Firewall Buffer Overflow Vulnerability”. Known Exploited Vulnerabilities Catalog, added 6 Feb 2025.
- ^ National Institute of Standards and Technology. “CVE-2020-15069 Detail”. National Vulnerability Database, published 29 Jun 2020.
- ^ Sophos. Advisories and fixes: community.sophos.com.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.107, percentile 95.8, 31 Oct 2026.
- CVE Program. “CVE-2020-15069”. The official CVE record.
This article is built from CISA’s catalog (version 2026.10.30), NVD’s record and FIRST’s scores, kept in HARD’s database and checked every morning. The plain English is HARD’s.