Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c170f57d82621bd…

MALICIOUS

PDF

74.4 KB Created: 2021-04-10 11:35:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 167e9b97b85d2cc3f19733982b31e358 SHA-1: ef296b86fc3c295c2324ccec41e00565deaa1a55 SHA-256: 7c170f57d82621bdb60ce6005dc343946352a9000eadb458fcee7d6a3e729ace
186 Risk Score

Malware Insights

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

The PDF contains numerous external links, many hosted on disposable domains, suggesting a link farm or phishing operation. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body, though heavily obfuscated, contains a question about unit conversion which is likely a lure to disguise the malicious nature of the embedded links.

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://dugedepap.ru/strik?utm_term=what+is+1+m2+in+cm2 PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4422135/normal_602e48ae662a1.pdfIn PDF document text
    • https://xutawolovunoka.weebly.com/uploads/1/3/0/7/130739399/bipozoxetodesijof.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4485435/normal_5fffc3a3ebc46.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4489843/normal_5ff671b1be14c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408482/normal_6056908b680ec.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379733/normal_5fe8ed2f87343.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416791/normal_604b1d729e59c.pdfIn PDF document text
    • http://kinorio5.xyz/1640078702fgdi6.pdfIn PDF document text
    • https://ravaratu.weebly.com/uploads/1/3/5/4/135401011/begijamujosexokog.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420448/normal_60462f29cfb73.pdfIn PDF document text
    • http://buyfastedcircle.xyz/931806638928lmlt.pdfIn PDF document text
    • http://bosnoslovnoejelaniekupit.xyz/jirizemin3jo8j.pdfIn PDF document text
    • http://bathforlegs.xyz/kosowiwenejutamwogm2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490534/normal_60530a1ba4c49.pdfIn PDF document text
    • http://wbigs.space/sauti_sol_video_songsd0v66.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367650/normal_602f540112205.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4476268/normal_6007e3ca561a1.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/791ea75c-48fc-4e4d-a7e9-d44193e01896/summer_infant_monitor_charger_29006.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/79845bc3-2f84-42f4-b680-6a15d2a45ef9/sat_subject_tests_dates.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d6639803-4938-4889-814c-f95d05ab7072/kagewinosobebiralilu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3515a608-10e7-496b-97ff-6c33de780196/suzuki_samurai_ome_lift_kit.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d87b4321-acad-4a66-9705-bc37a4217e67/75703280393.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c7c0109b-9ee8-49b5-a716-d22970669b12/blacks_law_dictionary_-_editions_1-9_pdf.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/69310907-9d01-4e9c-bd35-ba9907d640d0/color_psychology_blue_and_red.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_off0000e6aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6AA 5108 bytes
SHA-256: 949796534d2c39139d577bcb066d98334210f381e7f5b95967055768be5addb7
font_01_sfnt_off0000f7f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7F8 10744 bytes
SHA-256: 6ca6d9eb0a5b4058a1fff7d88e752f88ddc28db8ccf8fb1003226648859f35ec