CVE-2021-24559
CVE-2021-24559 is a medium-severity vulnerability in Patrickposner Qyrr with a CVSS 3.x base score of 5.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.
Key facts
- Severity: Medium (CVSS 3.x base score 5.4)
- EPSS exploit prediction: 0% (12th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2021-11471
- Weakness: CWE-79
- Affected product: Patrickposner Qyrr
- Published:
- Last modified:
Description
The Qyrr WordPress plugin before 0.7 does not escape the data-uri of the QR Code when outputting it in a src attribute, allowing for Cross-Site Scripting attacks. Furthermore, the data_uri_to_meta AJAX action, available to all authenticated users, only had a CSRF check in place, with the nonce available to users with a role as low as Contributor allowing any user with such role (and above) to set a malicious data-uri in arbitrary QR Code posts, leading to a Stored Cross-Site Scripting issue.
Frequently asked questions
- What is CVE-2021-24559?
- The Qyrr WordPress plugin before 0.7 does not escape the data-uri of the QR Code when outputting it in a src attribute, allowing for Cross-Site Scripting attacks. Furthermore, the data_uri_to_meta AJAX action, available to all authenticated users, only had a CSRF check in place, with the nonce available to users with a role as low as Contributor allowing any user with such role (and above) to set a malicious data-uri in arbitrary QR Code posts, leading to a Stored Cross-Site Scripting issue.
- How severe is CVE-2021-24559?
- CVE-2021-24559 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
- Is CVE-2021-24559 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-24559?
- CVE-2021-24559 affects Patrickposner Qyrr. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-24559?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- Does CVE-2021-24559 have an EU (EUVD) identifier?
- Yes. CVE-2021-24559 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-11471.
- When was CVE-2021-24559 published?
- CVE-2021-24559 was published on 2024-01-16 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:patrickposner:qyrr:*:*:*:*:*:wordpress:*:*
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