[PDFBOX-5395] Hangup in COSFilterInputStream.nextRange

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.0.25
• Fix Version/s: 2.0.26, 3.0.0 PDFBox
• Assignee: Tilman Hausherr
• Reporter: Aleksej Kozlov
• Created: 21/Mar/22 09:23
• Updated: 21/Apr/22 15:38
• Resolved: 30/Mar/22 02:58

Description

On some broken PDFs call PDSignature.getSignedContent never returns.
After exploring stacktrace I've found cycle in COSFilterInputStream.nextRange.

            while (this.position < this.ranges[this.range][0])
            {
                long skipped = super.skip(this.ranges[this.range][0] - this.position);
                this.position += skipped;
            }

Javadoc for skip says "The skip method may, for a variety ofreasons, end up skipping over some smaller number of bytes, possibly 0."
So, when skip returns 0 this cycle became infinite.
Tried in versions 2.0.25 and 3.0.0-RC1.