Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b6e271ad5d4eba9…

MALICIOUS

PDF

82.5 KB Created: 2021-09-02 19:11:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 26016f49ff9c92515dffb55ae18c10f2 SHA-1: bf60f44e49222fc9ce911fa2d9d009fbdbfdbb8c SHA-256: 6b6e271ad5d4eba93eea40914498894b04bedf8e13a3f4370fcb664a0b43d23c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links pointing to external websites, many of which host other PDFs. This behavior is indicative of a link farm designed to distribute malicious content or lead users to phishing sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://krisoc.ru/uplcv?utm_term=herramientas+manuales+para+construccion+civil PDF link annotation
    • https://www.agcontraincendios.es//ckfinder/userfiles/files/bikusope.pdfIn PDF document text
    • https://beyondpins.com/calisma2/files/uploads/binunenurinu.pdfIn PDF document text
    • https://secolink.sk/userfiles/file/xiraja.pdfIn PDF document text
    • http://meskerjager.nl/media/files/mamago.pdfIn PDF document text
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/op2n0u2usph43mi64ksi3a89q5/32737952974.pdfIn PDF document text
    • https://razvozka24.ru/wp-content/plugins/super-forms/uploads/php/files/ec19da1a2c5ea35c47f515191ee6c98c/44164416425.pdfIn PDF document text
    • https://tepihtrava.rs//files/35873733579.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/h9emv9o8qrpeiuanjp2uo8d9fj/36279259346.pdfIn PDF document text
    • http://alemotta.com/resources/original/file/wewugigujivigitumubavak.pdfIn PDF document text
    • http://fine-cottage.ru/userfiles/file/tarop.pdfIn PDF document text
    • http://serdceprirody.ru/userfiles/file/6697746476.pdfIn PDF document text
    • http://uniquestatues.com/clients/9/91/91c6e204ee4529d3b478b0717040545d/File/fexekonewume.pdfIn PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160838e9de4310---58657500096.pdfIn PDF document text
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/v0jles053ndvg61q6v2kn244vd/40328794427.pdfIn PDF document text
    • https://tipresentoio.it/images/file/82220572746.pdfIn PDF document text
    • http://pamatudarbai.lt/ckfinder/userfiles/files/fekanomobix.pdfIn PDF document text
    • http://fritz-fahrlaender.ch/download/dabufav.pdfIn PDF document text
    • http://ngocminhcnc.com/demo_thietbimay_24_7/upload/files/14444340305.pdfIn PDF document text
    • https://rougezenekar.hu/files/file/sobuvaletovixovepape.pdfIn PDF document text
    • https://netwindowvn.com/uploads/userfiles/file/vukiwuwotubitomitewipus.pdfIn PDF document text
    • https://tch.lu/files/files/pelipelevowi.pdfIn PDF document text
    • http://modern-pro.ru/files/file/sejutifo.pdfIn PDF document text
    • http://giacongcomposite.com/upload/ck/files/nanomufog.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000de74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE74 18148 bytes
SHA-256: b552972f3255da39743e7676d3aad4dd295bebe6c7e030dcd9671492be271ebd
font_01_sfnt_off00010be9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BE9 10692 bytes
SHA-256: 70f09f5e42239605a4bd14ad3fc38c3fe659635d2e7e6f9f2ba6fe07d21cd519
font_02_sfnt_off00012466.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12466 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1