In recent events, the security community has been stirred by the discovery of CVE-2020-19909. This security vulnerability has ignited discussions about the integrity and reliability of the CVE identification system. The incident, which unfolded on August 25, 2023, through an email to the curl-library mailing list, reveals the intricate web of issues surrounding the current state of CVEs and their association with the National Vulnerability Database (NVD).
The narrative begins with an email from Samuel Henrique, raising concerns about an unacknowledged CVE, specifically CVE-2020-19909, associated with a curl-related problem. Unlike the usual practice of curl project members filing and documenting their own CVEs, this particular instance has brought to light the shortcomings of the existing system.
A notable peculiarity of CVE-2020-19909 lies in its identifier, containing "2020" despite its recent emergence. Typically, CVEs are issued with the year of their registration, raising questions about whether this CVE is a delayed response to an older issue or an entirely new problem that wasn't properly addressed.
Upon inspection, the severity assigned to CVE-2020-19909 is strikingly high - a critical rating of 9.8, with 10 being the maximum severity. However, a closer examination of the description reveals that this assessment might be inaccurate. The vulnerability relates to an integer overflow in curl 7.65.2, attributed to a crafted value used as a retry delay. Closer scrutiny suggests this might not be the catastrophic security flaw that the severity rating implies.
Experienced members of the curl security team quickly recognized the issue from a previous report. In July 2019, a user named Jason Lee reported a similar problem involving an integer overflow in curl's --retry-delay option. The fix for this issue was introduced in curl 7.66.0, released in September 2019. The issue's resurgence and subsequent high-severity grading are points of contention in the discussion.
The emergence of CVE-2020-19909 within NVD's database has sparked a chain reaction. As information spreads across various platforms and databases that rely on NVD's data, a narrative of a severe security flaw circulates, potentially causing unnecessary alarm among users and developers. The incident underscores the significance of accurate, well-informed CVE ratings to prevent misinformation from proliferating.
In response to this incident, efforts to correct the situation have already begun. Notably, Ubuntu has marked CVE-2020-19909 as "not-affected," highlighting the divergence of opinion surrounding the severity of the issue. Meanwhile, the curl project and its members are committed to transparently addressing security vulnerabilities and sharing comprehensive information.
CVE-2020-19909 serves as a reminder of the complexities embedded within the CVE identification process. The incident raises concerns about the accuracy of severity ratings and the potential for misinformation to propagate across the security ecosystem. As discussions continue, the case highlights the need for collaboration, scrutiny, and adjustments in the CVE system to ensure the dissemination of accurate and reliable security information.