Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4a71692a1afee34…

MALICIOUS

PDF

106.1 KB Created: 2021-05-18 20:58:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: d355a51ccf20d4e6f140ea5bfd2abbfd SHA-1: 2e1dbd9b7674ce1b89166767f376825ed2d86226 SHA-256: f4a71692a1afee340a58421a568ec431e6b202b136997a2afb2427cd688b88e4
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable domains, indicating a link farm or phishing lure. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and numerous external links are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://jacksth.ru/strik?utm_term=miss+universe+2019+winner+last+question+answer PDF link annotation
    • https://jevebuna.weebly.com/uploads/1/3/4/5/134594548/9576679.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4483072/normal_5fdecb72e8c15.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4491148/normal_604a3ee988773.pdfIn PDF document text
    • https://futokiwusilo.weebly.com/uploads/1/3/4/4/134458686/visivedozawo.pdfIn PDF document text
    • https://mibugekokedepi.weebly.com/uploads/1/3/2/6/132682655/3617806.pdfIn PDF document text
    • https://radixukawatezod.weebly.com/uploads/1/3/4/6/134645496/vunuba_zazunubaz_muxukiwi.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4482189/normal_5ff55b331d67b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388827/normal_6041df75968fc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4480758/normal_6061db338ce49.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4407784/normal_603e655b11d2a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4504568/normal_60150a646d984.pdfIn PDF document text
    • https://sesumevikenaful.weebly.com/uploads/1/3/5/3/135346106/zavek_potufugigaxage_vovuloguluwajot_lalukesime.pdfIn PDF document text
    • https://puvebimu.weebly.com/uploads/1/3/4/3/134311544/fuvepo-dejudosefa.pdfIn PDF document text
    • https://samomalekadoj.weebly.com/uploads/1/3/1/4/131438786/raludo_dufopadupuv_navutekonak_fowewek.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460944/normal_60641cf479662.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470537/normal_6066bfdeb7563.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/58e12eaa-4d9d-4073-b7bf-dc0bc1bc7dd4/naduxubuluxuxonevo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7e227b25-f5a9-4e03-9cd6-cc21462a8c69/is_irobot_publicly_traded.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/812c0b8b-6b07-4353-92f8-d64be639d400/3406021449.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0a4ebe17-4e65-4afb-a95c-7a4e00c7a49a/jumokebexagiwukepin.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/808a820d-eced-4a66-a824-5564310c4d6a/66936415726.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dc944bf9-8096-4e23-ae1d-da954989d9eb/what_holds_the_atoms_in_a_molecule_together.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/afd3e64a-048b-4db3-a174-e919d5e1039e/vubafifepezojujonav.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7ed6e4fe-9076-43f6-be46-2eb7731b1168/guparowiz.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_off00015b44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15B44 5444 bytes
SHA-256: 8e68f69f25eafe9c59800fa9175aea052e675366923f1984caa11512cdb05baf
font_01_sfnt_off00016df8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16DF8 14720 bytes
SHA-256: e1a84fae04f7e58ab43797d4cb2de82ab4f1f032a60ed4bfac8171a4c77ac591