Malicious PDF — malware analysis report

Static analysis result for SHA-256 ce4d533e36bf0c2b…

MALICIOUS

PDF

69.9 KB Created: 2021-09-26 23:25:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 4453dba951b3335114548715d32afe8c SHA-1: c4fc4ed31b625353bd2712f0a9d8f944351fa97b SHA-256: ce4d533e36bf0c2b1d45a66b48735d36609e4ab39fb0b72b913cccd63d0fe281
156 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and link farm patterns, indicating an attempt to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. No scripts were extracted, but the PDF structure itself is used to facilitate the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 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://philabc.ru/uplcv?utm_term=milton+friedman+money+mischief+pdf PDF link annotation
    • https://casartigianiudine.busletter.it/ckfinder/userfiles/files/xejojivugugenin.pdfIn PDF document text
    • https://gaziemirkentkonseyi.com/upload/files/12837097834.pdfIn PDF document text
    • http://hongdanhaudio.com/luutru/files/kotewarafod.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/memavozivotabem.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613c39415af73---34335678954.pdfIn PDF document text
    • http://buren-kompanie.de/userfiles/files/9633957522.pdfIn PDF document text
    • http://connectcontrol.net/files/userfiles/files/86572706366.pdfIn PDF document text
    • http://nhuaduongnhapkhauaz.info/upload/files/94821513982.pdfIn PDF document text
    • http://impactpluslearning.com/ckfinder/userfiles/files/43667654044.pdfIn PDF document text
    • https://nazragame.com/calisma2/files/uploads/15833411845.pdfIn PDF document text
    • http://oxigensupplies.com/shipinc/userfiles/files/25340149976.pdfIn PDF document text
    • https://vallejardin.com/wp-content/plugins/super-forms/uploads/php/files/c4069c2d38a5531e25d8db3e347f9f1a/19613790793.pdfIn PDF document text
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/1f38a058b946295e4bf86c5e58942aef/78983033144.pdfIn PDF document text
    • https://hgb.se/filer/file/suwopikajemidajugodelanim.pdfIn PDF document text
    • http://sdes.in/uploads/milinelenuv.pdfIn PDF document text
    • https://lesrimaudieres.com/images/uploads/file/perovojavogururakif.pdfIn PDF document text
    • http://luchetti.it/userfiles/files/sunubesidelavisemowomos.pdfIn PDF document text
    • https://zoldlepes.hu/userfiles/file/vivibojaw.pdfIn PDF document text
    • http://gzperson.com/uploadfile/files/tugotofedi.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/16150c1f0e2dc2---lukamara.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/161471feedb09c---72605755614.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c2c6a40bd2---14210865102.pdfIn PDF document text
    • http://masan315.net/board/imagefile/file/mumezaxujofo.pdfIn PDF document text
    • http://lokalizacja-gps.pl/userfiles/file/3536477746.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_off0000b2fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2FB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB0D 14840 bytes
SHA-256: 944f2861ba790432bd5eeb8a3a410c5b242693efef902db403946d053141231a
font_02_sfnt_off0000f00a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF00A 10992 bytes
SHA-256: e9f02e87b0a4d12097e909db6a29110cbff6c278349bc5361919c9bc74a852e5