Malicious PDF — malware analysis report

Static analysis result for SHA-256 951c13101c355996…

MALICIOUS

PDF

92.1 KB Created: 2020-09-10 13:13:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2026-05-08
MD5: 56d71aa55ff33db9ae871fd3904af912 SHA-1: 26467844ca99e41ffb35ef2b9ea326180f0374d2 SHA-256: 951c13101c355996cc1781757cabfa486a7c2972594f2ff2a6a1fdbab8748013
202 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF file contains a critical heuristic firing for a malicious redirector link, specifically 'https://ttraff.link/wix?keyword=difference+between+biochar+and+charcoal+pdf'. Additionally, it exhibits characteristics of a PDF link farm, with numerous links pointing to external resources, many hosted on 'static.usrfiles.com'. The document body, though heavily obfuscated, contains the same URL, suggesting it's the primary lure. The urgency lure heuristic further supports the deceptive nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 6

  • 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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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.link/wix?keyword=difference+between+biochar+and+charcoal+pdf In PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://static.usrfiles.com/ugd/0dd040_3795651af192442cb0ff9d2e3cbc7dc9.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/3402b1_aa1d16ce5f504a7a82c144ffbddb5bf1.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/44b221_3cba869c4dbf40e7851dc1cd88fe04b4.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/6166c9_297c80acaaa44e3ab16e48677ff7be25.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/225520_80cbc333ac4d4e8c9abb5536494c2d6a.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/ff2e72_c990c9c92ac34ef99c20868e9c4b2c38.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/a0905b_103edbf2401e47fc9343f7080e7fd231.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/0ad6c7_657615fd48d3492f883d072a7a451bc9.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/1e533a_3ff7083cc9f14ff8b55aeac76f2ac166.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/9f6a24_8be4632647d14aba886fa1fbca22ec26.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/ea2f88_514ae38970944089a15ce524e467cce0.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/67f5f7_7b3ef812f05e485093cdec618a78d1ce.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/b910ae_fce62e0dc7a047468f5d5ca8f3836380.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/4458/6140/files/ctet_syllabus_2018_in_english.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/6686/7362/files/sql_server_2020_alwayson_availability_groups_step_by_step.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000112f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112F7 5296 bytes
SHA-256: 9a9da24dd61f81c5018f87f7f19c8be5cbd8c71334f997b097c51f42d77ee737
font_01_sfnt_off0001250c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1250C 11924 bytes
SHA-256: 4559c83ec91cc734dd7847ab2d14ab562990fa5f8a435bf270269c8fe0d851fb
font_02_sfnt_off00014d8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14D8E 16148 bytes
SHA-256: aabbb95e4258a1bccfe6759090a0a8b97a33e8154131110566ffb2eaa8fdb080