Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d51b011d7cf4d79…

MALICIOUS

PDF

83.9 KB Created: 2021-09-02 16:53:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f9a6d93bfdab62c87f854a015d3a528f SHA-1: ea392baa5d4c9f000b3db5d7ed534b0af9f5a5b8 SHA-256: 3d51b011d7cf4d7971267d6147a30e6d15eb5165df02d1966a138afc5c47a528
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and multiple external URIs, many of which point to potentially compromised websites hosting PDF files. The heuristic 'SE_PASSWORD_ARCHIVE_LURE' indicates the document likely instructs the user to download an archive, suggesting a multi-stage attack where the password protects the payload from initial scanning. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://egyiksem.hu/uploads/file/19295941418.pdf
    • http://www.awakohchang.com/image/upload/File/1916630340.pdf
    • http://cpghollywood.com/userfiles/files/lozegotonetewitonimilop.pdf
    • https://gazelletr.com/userfiles/files/dagawidejet.pdf
    • http://xn--9w3b11kh5l.com/ckupload/files/totirosubamisegito.pdf
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16080983f65e42---rilarelugovefamuto.pdf
    • http://underbutter.cz/download/foto/67651186127.pdf
    • https://deepex.hu/hirek/files/62755383393.pdf
    • http://markasib.ru/ckfinder/userfiles/files/fozovojififefak.pdf
    • http://golden-candies.ru/webroot/files/files/zosaxotenizo.pdf
    • http://computerdoki.hu/user/file/gavurakixozemegoxat.pdf
    • http://rungrawin-itt.com/userfiles/files/85983999729.pdf
    • http://toyotarenta.net/FileData/ckfinder/files/20210716_4F377562AACA1F3D.pdf
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b74c7a4dd55---zomabeledepotamotiwu.pdf
    • http://hsound.ro/images/custom/file/54967026423.pdf
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d9c71082049---18788426460.pdf
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/16075eb003c6b8---97475489812.pdf
    • https://giriconsultancy.com/content_files/files/gujedujeve.pdf
    • http://t-p-fortune.com/userfiles/file/24573769241.pdf
    • http://to-kajihan.net/js/upload/files/duketubiwodug.pdf
    • https://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/04n7i0tnu5vr5tt6mogkecnhnj/xozajapib.pdf
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/lcoqmtq4ra2hnml8tueu896oe3/58386375172.pdf
    • https://ip-pharma.net/data/files/59284057057.pdf
    • http://heninrealty.com/userfiles/files/54722894981.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=salton+electric+pressure+cooker+recipes+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dcdd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDCDD 16792 bytes
font_01_sfnt_off0000f4f4.bin
813790373c5e455f5d145d71c6e90898541053068a5963728588efe375089ac0
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4F4 10880 bytes
font_02_sfnt_off00010e2f.bin
684ba26acf2528b2dad7f1286c4c3cea57c60a5b1ce196e810212af3f2c1babf
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E2F 19600 bytes