Malicious PDF — malware analysis report

Static analysis result for SHA-256 daaf1462cc39477a…

MALICIOUS

PDF

42.7 KB Created: 2020-08-29 10:00:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0cb68e3975f43cfe0bb4b86145ee5251 SHA-1: debd38f4e9deb96b325adb7b5485580444d0b242 SHA-256: daaf1462cc39477a97719edeb19ef6526d5a4bf868e790871d4e6f5700826227
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious due to a critical heuristic firing for a malicious redirector link. The document body contains text that appears to be SEO spam, and the PDF structure reveals a large number of embedded links, many pointing to a link farm hosted on static.usrfiles.com. The primary malicious IOC is the redirector URL, which is likely used to funnel victims to further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.ru/wix?keyword=xem+phim+th%25C3%25A0nh+th%25E1%25BA%25ADt+v%25E1%25BB%259Bi+t%25C3%25ACnh+y%25C3%25AAu+c%25C3%25B3
    • https://static.usrfiles.com/ugd/b8c837_208b6b9e66bc4a1ba5edfd7a15364afd.pdf
    • https://static.usrfiles.com/ugd/b8c837_4edfeac9870e4392bf67c77766a62750.pdf
    • https://static.usrfiles.com/ugd/b8c837_a98d07a1afca46ea9badc44f6f3226de.pdf
    • https://static.usrfiles.com/ugd/b8c837_31a8c369cba9457ca7d3468049512af9.pdf
    • https://cdn.shopify.com/s/files/1/0463/3853/9682/files/gitaseronukusuv.pdf
    • https://cdn.shopify.com/s/files/1/0435/6017/3717/files/church_flyers_psd_free.pdf
    • https://cdn.shopify.com/s/files/1/0438/1884/4322/files/28641210157.pdf
    • https://static.usrfiles.com/ugd/b8c837_8b921cfaf69c4d6ab3c0c9fec767e3f7.pdf
    • https://static.usrfiles.com/ugd/b8c837_4820d587703c45f1bae3d88223922d31.pdf
    • https://static.usrfiles.com/ugd/b8c837_475ea5f403834e1c956264d8c682346e.pdf
    • https://static.usrfiles.com/ugd/b8c837_a1d869dbd2f34fbbbc4f0ef829ee6281.pdf
    • https://static.usrfiles.com/ugd/b8c837_709ba223626e4587b9862a591c30896b.pdf
    • https://static.usrfiles.com/ugd/b8c837_3209c11817454c42a95375fe3333f0bc.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000594e.bin
7035bff7b4c48172414ea9953fef1f907e596db8ff1606242a3d557fe75d3912
pdf-font-stream PDF embedded font (sfnt) at offset 0x594E 5792 bytes
font_01_sfnt_off00006bad.bin
5cf00c7ad46d6167bc22973bac9baeff3be1ea719a49fca6925f6a8b91e342b7
pdf-font-stream PDF embedded font (sfnt) at offset 0x6BAD 22048 bytes