Malicious PDF — malware analysis report

Static analysis result for SHA-256 e43a06d6ef72f526…

MALICIOUS

PDF

72.5 KB Created: 2021-03-30 22:54:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 0aafb461f86cae40b1aa2b1fe81b3e3c SHA-1: 4774faa341673b0128cc522f55eb22e0c320a45e SHA-256: e43a06d6ef72f526bb6ea80bf0f72f95e4bad8c58ea11bc1be8acadfa2ca01dc
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many pointing to disposable domains, suggesting a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded URL `https://mezovuduw.ru/strik?utm_term=anesthesiologist%2527s+manual+of+surgical+procedures+6th` is likely part of the attack chain, aiming to redirect the user to a malicious site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://mezovuduw.ru/strik?utm_term=anesthesiologist%2527s+manual+of+surgical+procedures+6th PDF link annotation
    • http://good-production18.site/fire_and_blood_book_summarywb4th.pdfIn PDF document text
    • http://miwewumexurigan.sportsontheweb.net/11916395139.pdfIn PDF document text
    • http://cleanup-sale.site/pugodesifinjo5t.pdfIn PDF document text
    • http://totalcreditreport.info/canopus_advc-_110_manualr93bz.pdfIn PDF document text
    • http://budivev.scienceontheweb.net/zujavujep.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://74269c25-1731-4359-90d4-804f54ef9c1c.filesusr.com/ugd/b5973a_469cdbd1b09e40e598e0a87fd7b147df.pdf?index=trueIn PDF document text
    • https://9d1e48ad-bcd7-4831-9b7b-7108443a63b6.filesusr.com/ugd/136d07_5995451388544cb1a09421f09217cf0b.pdf?index=trueIn PDF document text
    • https://50aad03f-9d2a-47e6-be13-abd12f321b17.filesusr.com/ugd/3fd638_f8fa8dcadbce4e30a1b7afabf324629b.pdf?index=trueIn PDF document text
    • https://7404da97-7fcf-4d5f-9d5f-3f8644e6773a.filesusr.com/ugd/35f767_4a5c3b4d3b524393a1500dc0f9c24f24.pdf?index=trueIn PDF document text
    • https://71e5fc8e-cc9a-4633-96c3-2c70acd464d0.filesusr.com/ugd/f08e01_751c30ce14db4156bf7664f7fcb28bc6.pdf?index=trueIn PDF document text
    • https://201a0bc5-0eb3-4135-8969-828875a6b07d.filesusr.com/ugd/607883_f6473c0e869041d494af43727d87165b.pdf?index=trueIn PDF document text
    • https://3e1d1bad-f645-4ebd-ac75-469e7ff7c972.filesusr.com/ugd/e745be_8fcc01ec2ecb4969b62fa2c76af9c4bd.pdf?index=trueIn PDF document text
    • https://979cd01f-16ea-4d2c-b189-234964c95597.filesusr.com/ugd/d4c4cf_00c584bb665a4bc5a2ca5165b1b07178.pdf?index=trueIn PDF document text
    • https://044ec7df-721b-4788-b209-87474a3fcb06.filesusr.com/ugd/60ffa2_154619d3fc844e2083b9c87f3ed5b3fd.pdf?index=trueIn PDF document text
    • https://bf130ee1-1463-4c69-9604-1b23772ced92.filesusr.com/ugd/b4609a_c55a9e15c77544fea744bce58aab77a6.pdf?index=trueIn PDF document text
    • https://b9264059-5ce6-458a-812b-58b21e0c51d1.filesusr.com/ugd/9a3dc1_7128d993e9274548aecf3ba508e3b5e0.pdf?index=trueIn PDF document text
    • https://9ef77391-fdd1-48d8-ba15-364b07375333.filesusr.com/ugd/ebefdf_cde4750f1c0c48f78ce58a7b8e01c02c.pdf?index=trueIn PDF document text
    • https://68fdcf0a-b1f0-4758-9edf-48d2be6d990b.filesusr.com/ugd/ac51ce_38a509e8f6e8497a932684a3ae073603.pdf?index=trueIn PDF document text
    • https://bf808793-8b46-4c54-8b11-319763181fa0.filesusr.com/ugd/0d018b_4e0c7a276390466e9b9c31a893a911a4.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_off0000dbf2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBF2 5744 bytes
SHA-256: 53eebdd95de92d1e4b7928f888334ed43fe029616140c57f5f96210b5c810039
font_01_sfnt_off0000ef5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF5E 10900 bytes
SHA-256: af8243b366cb49c9e7539699c532dc9d6b8753c4b7b4782a84659ef7850b4513