# What is CVE-2020-28948? > CVE-2020-28948 is a high-severity flaw (CVSS 7.8) in Archive Tar from PHP, published on 19 November 2020. It is not on the list of flaws known to be exploited today. The latest forecast puts its chance of use in the next 30 days at 47%. If you run an affected version, plan in the vendor’s fix. Canonical page: https://www.precursorintelligence.com/what-is/cve-2020-28948 ## At a glance - **Verdict:** Fix this soon. Not confirmed as exploited yet, but serious or likely enough that it should not wait for a quiet month. - **Precursor Intelligence risk score:** 45 out of 100 (Medium); action: Plan remediation. Kept up to date as the evidence changes. - **Severity:** High (CVSS 7.8 out of 10) - **Known to be exploited:** No, not on the list of flaws known to be exploited today - **Chance of use in the next 30 days:** 47% (latest exploit-likelihood forecast) - **Published:** 19 November 2020 - **Record last updated:** 7 November 2023 - **Main product:** Archive Tar from PHP - **Affected products:** 4 ## What is CVE-2020-28948? In plain terms An attacker has to be already on the device without logging in, but a person has to take an action first. If it works, the attacker can read data, change data and take it offline. ### The official description Archive_Tar through 1.4.10 allows an unserialization attack because phar: is blocked but PHAR: is not blocked. ### What kind of flaw is it? - CWE-502: Deserialization of Untrusted Data ### How an attack on it works - Where an attacker can be: Already on the device - How hard it is to pull off: Easy: no special conditions - Login needed first: No login needed - Does someone have to click: Yes, a person has to take an action - What an attacker gets: Can read data, change data and take it offline Severity vector: `CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H` ## Is CVE-2020-28948 being exploited? Not that we know of It is not on the list of flaws known to be exploited today. The latest forecast puts the chance of it being used in the next 30 days at 47%. That can change at any time, which is why we keep watching. Exploit likelihood over the last 7 days: 47%, 47%, 47%, 47%, 47%, 47%, 47%. ### Timeline - 19 November 2020: Published - 7 November 2023: Record last updated - 19 November 2025: Exploit likelihood fell - 22 November 2025: Exploit likelihood jumped ### How Precursor Intelligence ranks it CVE-2020-28948 scores **45 out of 100 (Medium)**, with the action "Plan remediation". Every published flaw gets a risk score from 0 to 100, kept up to date as the evidence changes. Four things go into the score, from the one that counts most to the ones that count less: - Evidence it is being exploited: biggest factor - How severe it is: strong factor - How widely exposed it is: key context - Real threat activity around it: key context 85 and above is Critical. Anything confirmed as exploited is always marked for an emergency patch, whatever its score. When this flaw matches software you track, it lands in your list with its score and the reasons behind it. ## Who is affected by CVE-2020-28948? The published record lists 4 products. Versions are as published: "before 1.4.11" means every version up to, but not including, 1.4.11. - [Archive Tar](https://www.precursorintelligence.com/product/php/archive_tar) by [PHP](https://www.precursorintelligence.com/vendors/php) (Application): before 1.4.11 - [Fedora](https://www.precursorintelligence.com/product/fedoraproject/fedora) by [Fedoraproject](https://www.precursorintelligence.com/vendors/fedoraproject) (Operating system): 32, 33, 34, 35 - [Drupal](https://www.precursorintelligence.com/product/drupal/drupal) by [Drupal](https://www.precursorintelligence.com/vendors/drupal) (Application): 7.0 to before 7.75, 8.0.0 to before 8.9.10, 9.0.0 to before 9.0.9 - [Debian Linux](https://www.precursorintelligence.com/product/debian/debian_linux) by [Debian](https://www.precursorintelligence.com/vendors/debian) (Operating system): 9.0, 10.0 ## How do I fix CVE-2020-28948? 1. **Check whether you run it.** Compare your versions with the affected products above. Not sure what you run? Precursor Intelligence can work it out from your public website, or you can pick it from a list. 2. **Apply the vendor’s fix.** Install the latest update from the vendor. The references list where the vendor has published details. 3. **If you can’t patch today.** Follow any mitigation the vendor publishes, and limit who can reach the affected system from the internet until the update is in. 4. **Keep an eye on it.** Track the product and we tell you as soon as we spot this flaw on the list of exploited flaws, or a jump in its exploit likelihood. ### References - [github.com](https://github.com/pear/Archive_Tar/issues/33) (Exploit, Issue tracking, Third-party advisory) - [lists.debian.org](https://lists.debian.org/debian-lts-announce/2020/11/msg00045.html) (Mailing list, Third-party advisory) - [lists.fedoraproject.org](https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/42GPGVVFTLJYAKRI75IVB5R45NYQGEUR/) - [lists.fedoraproject.org](https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4V35LBRM6HBCXBVCITKQ4UEBTXO2EG7B/) - [lists.fedoraproject.org](https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5KSFM672XW3X6BR7TVKRD63SLZGKK437/) - [lists.fedoraproject.org](https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KWM4CTMEGAC4I2CHYNJVSROY4CVXVEUT/) - [lists.fedoraproject.org](https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NBYZSHYTIOBK6V7C4N7TP6KIKCRKLVWP/) - [lists.fedoraproject.org](https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VJQQYDAOWHD6RDITDRPHFW7WY6BS3V5N/) - [security.gentoo.org](https://security.gentoo.org/glsa/202101-23) (Third-party advisory) - [debian.org](https://www.debian.org/security/2020/dsa-4817) (Third-party advisory) - [drupal.org](https://www.drupal.org/sa-core-2020-013) (Third-party advisory) ## Questions ### What is CVE-2020-28948? CVE-2020-28948 is a high-severity flaw in Archive Tar from PHP, published on 19 November 2020. An attacker has to be already on the device without logging in, but a person has to take an action first. If it works, the attacker can read data, change data and take it offline. ### How serious is CVE-2020-28948? It scores 7.8 out of 10 on the CVSS severity scale, which is high. Our risk score for CVE-2020-28948 is 45 out of 100, which is Medium. Its action is "Plan remediation". Not confirmed as exploited yet, but serious or likely enough that it should not wait for a quiet month. ### Is CVE-2020-28948 being exploited? It is not on the list of flaws known to be exploited today. The latest forecast puts the chance of it being used in the next 30 days at 47%. That can change at any time, which is why we keep watching. ### Which versions does CVE-2020-28948 affect? For Archive Tar from PHP: before 1.4.11. The record lists 4 products in all, each with its versions, under "Who is affected" on this page. ### How do I fix CVE-2020-28948? Install the update the vendor names in its advisory. If you can't patch today, follow the vendor's mitigation and limit who can reach the affected system from the internet. ## Does CVE-2020-28948 affect you? Precursor Intelligence keeps checking for you: - **Tell us what you run.** Pick your software from a list, or let us work it out from your website. - **We match it to every flaw.** Over 400,000 published flaws, checked against your list. - **Ranked by real-world risk.** Every flaw gets a 0 to 100 risk score, kept up to date, led by evidence criminals are using it. - **Told as soon as we know.** An alert by email, in the app or by webhook to your own tools. Start free (no card, nothing to install): https://www.precursorintelligence.com/register Book a demo: https://www.precursorintelligence.com/contact