Malicious PDF — malware analysis report

Static analysis result for SHA-256 2339c50e8d9bfa1a…

MALICIOUS

PDF

87.6 KB Created: 2021-04-03 12:56:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 0b875505f9af6665e45f12d282be7c53 SHA-1: 2c1fcf3411c0ae750be5b4e4e4e7e0e18c058116 SHA-256: 2339c50e8d9bfa1a3261bb2660ef9e3fc04acc681a048adfa5a814d790633081
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous external links, many of which are part of an SEO link farm designed to redirect users. The primary redirector URL, 'https://zajinet.ru/strik?utm_term=how+long+to+assemble+power+wheels+dune+racer', is identified as a lure for free downloads. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest a phishing or malicious redirection attempt, likely leveraging embedded JavaScript for obfuscation or redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://zajinet.ru/strik?utm_term=how+long+to+assemble+power+wheels+dune+racer PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4493917/normal_5ff3817bc27dc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427828/normal_6012b309f12bf.pdfIn PDF document text
    • https://xemamipu.weebly.com/uploads/1/3/0/8/130813095/lobipa.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4479222/normal_5fdcb42b3df89.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4454299/normal_5fcda89ecf65b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4494877/normal_5fd7d92b5be7f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4385216/normal_5fe2504df3452.pdfIn PDF document text
    • https://fidevawane.weebly.com/uploads/1/3/0/8/130814252/5894719.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://c0771fee-1ba5-4dbf-bba5-a775c3d44c03.filesusr.com/ugd/544e7e_ba9d1a3dc50a449d86f1f7dd4d6ec935.pdf?index=trueIn PDF document text
    • https://0ea1ff7f-05b3-43a2-9744-178351a05ed1.filesusr.com/ugd/01f9b9_a1f405cfc2b94bec93857cabc28d1b07.pdf?index=trueIn PDF document text
    • http://befugoj.epizy.com/pokelokezelabavoguxom.pdfIn PDF document text
    • https://1b53f64c-3596-40ff-86ea-95cec8902569.filesusr.com/ugd/838e7e_582681070cd04c9e9618f1784f45dc08.pdf?index=trueIn PDF document text
    • https://c0b8f06b-4e98-4d3d-89ef-2f08caba629a.filesusr.com/ugd/0c8cc8_3849ae6555c94c13a9b57bbab25c0165.pdf?index=trueIn PDF document text
    • http://joriboka.epizy.com/billboard_2018_full_show.pdfIn PDF document text
    • https://b40f07b9-a98f-42b6-a6e2-5dc2c82ebb0e.filesusr.com/ugd/e949ea_c4afced73b3f4ac7baa8eea8b950eec0.pdf?index=trueIn PDF document text
    • https://cf268418-7549-4780-9cff-e39e61b5276c.filesusr.com/ugd/0b1cf2_97ad1d9230a4434491a4d43dd50d3e5a.pdf?index=trueIn PDF document text
    • https://63d876aa-455f-4c41-9c38-50747f3e0b95.filesusr.com/ugd/a220d5_16ccea96a53b46e3a0209847bf4491d0.pdf?index=trueIn PDF document text
    • https://6843e3eb-5573-46e1-90a0-370cfc2b4a0d.filesusr.com/ugd/89b1bc_802465b89ccd47b9912261a3b9dd4d02.pdf?index=trueIn 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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010b31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B31 5516 bytes
SHA-256: e2b48644aea6ebbf2b0cb04ca2f7ee58c58240d1fd288a459ea2e0b91c761924
font_01_sfnt_off00011dce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DCE 10928 bytes
SHA-256: ca053882217297719d8f9e8447898a609e81da1bef0a0e95db992bca7df53172
font_02_sfnt_off00014300.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14300 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f