Malicious PDF — malware analysis report

Static analysis result for SHA-256 f2f50be424740485…

MALICIOUS

PDF

77.3 KB Created: 2021-04-19 18:41:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 4d2d7dcfdd5a7fab59b3e4d23e4fb507 SHA-1: 238e8204c541fcf9931cefd1bd41beea42061ad5 SHA-256: f2f50be424740485f61dfc31f8cdec79a01ce829221416f8fbd92693064594bc
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links pointing to various PDF documents hosted on disposable domains, indicating a link farm or SEO manipulation tactic. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution through these linked documents. No scripts were extracted, but the presence of numerous external URLs is a primary indicator of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://vilenefex.ru/strik?utm_term=basics+of+software+architecture+%2526+design+patterns+in+java+download PDF link annotation
    • https://duzigolanulemo.weebly.com/uploads/1/3/2/6/132680867/gafovanesidifa_wujapudukadad_dugewuso.pdfIn PDF document text
    • https://waruzakelejabu.weebly.com/uploads/1/3/4/6/134600446/c0017ee1d46c.pdfIn PDF document text
    • https://larekupexog.weebly.com/uploads/1/3/4/8/134884129/3803544.pdfIn PDF document text
    • https://wagezulixi.weebly.com/uploads/1/3/2/6/132695300/setexezik_riwote.pdfIn PDF document text
    • https://kowijifeno.weebly.com/uploads/1/3/5/3/135390944/b694bd814c3.pdfIn PDF document text
    • https://silepokow.weebly.com/uploads/1/3/4/3/134366863/5924f3142b.pdfIn PDF document text
    • https://budozawepolok.weebly.com/uploads/1/3/4/8/134852557/01c22420989d3c0.pdfIn PDF document text
    • https://rotisozag.weebly.com/uploads/1/3/4/6/134679288/6971028.pdfIn PDF document text
    • http://vashobereg.com/how_are_folk_culture_and_popular_culture_establisheduba2f.pdfIn PDF document text
    • https://jabenawonidibe.weebly.com/uploads/1/3/5/3/135385032/7779559.pdfIn PDF document text
    • https://vuriluwaloseg.weebly.com/uploads/1/3/4/4/134492921/0c48be761b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4469630/normal_6032e44d5f735.pdfIn PDF document text
    • http://sandwichhq.club/ap_psychology_exam_review_sheet_confusing_pairs_answersqhfqw.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412891/normal_60146f33bfc4e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4448124/normal_5ffba0be5eb36.pdfIn PDF document text
    • https://vogaxuruxav.weebly.com/uploads/1/3/4/3/134352923/225153.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4480755/normal_602a1e37c2c2f.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://849bdae7-2456-4570-9e2a-fc769e7e49ad.filesusr.com/ugd/2074c9_b0f8d84f3820415d9eeb4f1df7d47b01.pdf?index=trueIn PDF document text
    • https://9cf5cc10-3c2e-4e30-ae6b-73ed7beed88a.filesusr.com/ugd/5c2b46_9ca654e301ce4fbfaaa00bbec867ee47.pdf?index=trueIn PDF document text
    • https://a04ad255-06d6-4b17-97e7-91173d300295.filesusr.com/ugd/6864df_8f86f33c08184681a7556c65dce1cde2.pdf?index=trueIn PDF document text
    • https://b354d503-40d1-4c97-84b4-bc0b16c12f35.filesusr.com/ugd/8c7d07_49d3b23e1e8f47e5ac71e685175171b7.pdf?index=trueIn PDF document text
    • https://4868a29a-6d77-448d-a9c5-bc5c6a1713c3.filesusr.com/ugd/060e50_e36235cc146d48acb6448bc45f7000c8.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f03b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF03B 5076 bytes
SHA-256: ebc945779d7549c59e1b16400fbff9be63da4e78e13078acc6febc219504aa38
font_01_sfnt_off0001018f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1018F 11212 bytes
SHA-256: fcbc8f59ad926b9daca00148849acc0b639dc9952ac4cf764beaa0af4fef1b0b