Malicious PDF — malware analysis report

Static analysis result for SHA-256 221cbcf7b575aedc…

MALICIOUS

PDF

44.5 KB Created: 2020-08-31 12:38:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fd22865cc54d439dc5af9205d1109a93 SHA-1: b73906cafebdef6f328e78443ba38deb8be6ac17 SHA-256: 221cbcf7b575aedcf8c5d83d81a4420fa2e5c8fe91cb34e4cf5d63c1f8d17eb2
152 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by an ML classifier with high confidence. It contains a significant number of embedded links, with one pointing to a known malicious redirector (ttraff.ru). The presence of a large link farm, many pointing to benign Shopify URLs, suggests an attempt to obscure the malicious destination or engage in SEO poisoning. No scripts were extracted, but the primary attack vector appears to be the malicious redirection link.

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=gateway+fx6840+15e
    • https://cdn.shopify.com/s/files/1/0430/8808/5145/files/flat_inventory_template_word.pdf
    • https://cdn.shopify.com/s/files/1/0432/6742/4416/files/73511897007.pdf
    • https://cdn.shopify.com/s/files/1/0428/2492/5347/files/tesulorora.pdf
    • https://cdn.shopify.com/s/files/1/0432/0899/9074/files/45017868024.pdf
    • https://cdn.shopify.com/s/files/1/0433/6179/6248/files/44884643945.pdf
    • https://cdn.shopify.com/s/files/1/0434/8447/9641/files/abstract_algebra_cyclic_groups.pdf
    • https://cdn.shopify.com/s/files/1/0434/3244/4056/files/7681644593.pdf
    • https://cdn.shopify.com/s/files/1/0431/2471/9773/files/momiluxivuginorov.pdf
    • https://cdn.shopify.com/s/files/1/0437/6972/5080/files/notice_debroussailleuse_stihl_fs_44.pdf
    • https://static.usrfiles.com/ugd/0a593f_59dea0ad2a964b97a42c4b432fa8f6b7.pdf
    • https://static.usrfiles.com/ugd/b8c837_f2b9532331dc4e2fb6faa92178c372c5.pdf
    • https://static.usrfiles.com/ugd/01bc73_f34cfd9bebe44c14a940609a9f6a9bb0.pdf
    • https://static.usrfiles.com/ugd/80bfa9_e00035616e024f16974ddd57f94d29a1.pdf
    • https://static.usrfiles.com/ugd/a107db_220093242a164a20803b83bf06940918.pdf
    • https://cdn.shopify.com/s/files/1/0450/2405/1358/files/storytelling_techniques.pdf
    • https://cdn.shopify.com/s/files/1/0434/5665/9617/files/saxidifipis.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_off00006f83.bin
61d52ce79b534535102029610491eac2e2c19fc5ba0470273bc9509950643f85
pdf-font-stream PDF embedded font (sfnt) at offset 0x6F83 5500 bytes
font_01_sfnt_off00008288.bin
0ed4b0d68e9721856dc8413d4c4f747845ca000136b00f585c8593744fbae140
pdf-font-stream PDF embedded font (sfnt) at offset 0x8288 10164 bytes