Malicious PDF — malware analysis report

Static analysis result for SHA-256 27a78e08c028e183…

MALICIOUS

PDF

71.8 KB Created: 2021-04-03 04:21:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: f8de36c9b07976ede70e35b470d88674 SHA-1: 5f6c7857e27912221ba862b5153a65b7bb1dcb3c SHA-256: 27a78e08c028e183f3abbdcdedabdade1cc1cf55426fd1c1e50783a4fcf8f141
244 Risk Score

Malware Insights

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

The PDF document contains a large number of embedded links, many of which point to disposable hosting services or known redirectors, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a phishing or redirection attack.

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
  • 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.
  • 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.
  • 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://dafemum.ru/strik?utm_term=how+to+relieve+jumper%2527s+knee In PDF document text
    • https://lupemofuxuxutuj.weebly.com/uploads/1/3/1/3/131383332/kefaxutesesut.pdfIn PDF document text
    • https://kiruxujekan.weebly.com/uploads/1/3/2/7/132740547/nikirepu.pdfIn PDF document text
    • https://vesepogexaxun.weebly.com/uploads/1/3/0/7/130740074/zivepivuwuwo_wejed_gilukazojej_tanuw.pdfIn PDF document text
    • https://lewelekokoje.weebly.com/uploads/1/3/4/3/134333059/nojat.pdfIn PDF document text
    • https://bikonate.weebly.com/uploads/1/3/4/7/134715396/1874708.pdfIn PDF document text
    • https://zewosesivate.weebly.com/uploads/1/3/4/5/134591998/8524706.pdfIn PDF document text
    • https://wekosidofanepa.weebly.com/uploads/1/3/2/6/132696212/wedul-xovipeguzubunap-salifedesimed.pdfIn PDF document text
    • https://marizezibafive.weebly.com/uploads/1/3/4/8/134865590/bukiburi_gipobege.pdfIn PDF document text
    • https://rupogasonewu.weebly.com/uploads/1/3/4/6/134653860/tafelefakuvuwakenab.pdfIn PDF document text
    • https://dowililob.weebly.com/uploads/1/3/4/5/134518502/8f31e3539cc05.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://691dfa98-c543-4342-b77d-a3d7fbf094aa.filesusr.com/ugd/d55835_7d4d9c2e284040cdb57587fd881f4743.pdf?index=trueIn PDF document text
    • https://a5a8f6e1-24ae-425c-880d-6f4079e3c376.filesusr.com/ugd/035627_29b90ed3c87944b49d174894cd7e14df.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/wakuzidi/81809537995.pdfIn PDF document text
    • https://s3.amazonaws.com/tapexiw/pagewriter_tc70_service_manual.pdfIn PDF document text
    • https://78f121e6-5824-477f-9480-4bf23eba804c.filesusr.com/ugd/9564ad_5b281593a6e445098332a2a426758860.pdf?index=trueIn PDF document text
    • https://05e27880-d5e1-4d3d-8428-ba943e9300bc.filesusr.com/ugd/b56239_7be551eccd9b47aabee7bae66ba31701.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/vunizi/expressvpn_android_tv.pdfIn PDF document text
    • https://s3.amazonaws.com/nemafu/free_printable_mermaid_invitation_template.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dd3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD3C 5044 bytes
SHA-256: 95af208bc575288003156562c183fbb5790c3cf23cb96c9597cfa17346b4694c
font_01_sfnt_off0000ee6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE6B 10440 bytes
SHA-256: d41684c300bb2a33599d7fa2e0ffe5a84ab6896895e260e378a84bfecd19a59c