Malicious PDF — malware analysis report

Static analysis result for SHA-256 04431ab6294e8f6b…

MALICIOUS

PDF

89.8 KB Created: 2021-06-26 21:30:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2299d5b368ae2af3ea85d40ea8725369 SHA-1: df4f4c09e03695bd1005bbeaf3816c0ccbb1d548 SHA-256: 04431ab6294e8f6bb7c886b427193c45d562b7f3da11abe983eba33b93386e8f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites and disposable hosting, indicative of a link farm used for phishing or malware distribution. The ClamAV detection and ML classifier strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are sufficient to infer a malicious link-farming and potential distribution attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9765

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://laborke.ru/uplcv?utm_term=polygon+word+problems
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba467188924---tugipesawo.pdf
    • https://bayihoki99.com/contents//files/87458801364.pdf
    • http://china-hold.com/UploadFile/file/20210522051835639.pdf
    • https://nnkcreations.com/userfiles/file/75825443115.pdf
    • https://grand-forge.ru/wp-content/plugins/super-forms/uploads/php/files/015cbe102e128abd2d7d52cf9df7f352/litijoseb.pdf
    • http://mobilesamara.com/img/files/file/numasorebe.pdf
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a63d216c24---dimezozatolimisomuk.pdf
    • https://homini.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160869b428192f---98747741319.pdf
    • https://fokusmedia.com/images/uploads/91709270059.pdf
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b9ffa85c587---22971567029.pdf
    • http://kaies.cn/upfiles/file/95612056646.pdf
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/mik53q8f4e33nr5khaq6lhmd22/55155332822.pdf
    • https://www.americansummercamps.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7de663e69---6326698999.pdf
    • https://aspaeng.com/files/image/files/wefosumufowabujanidik.pdf
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/16079bd22a663b---97850175333.pdf
    • http://gulfcoolcontracting.com/uploads/userfiles/file/file/78262627393.pdf
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/5708e1f671fb4a6ea6959c17d06b577a/nepozuderopapebenutelexe.pdf
    • https://rajaunited.com/contents//files/44697311469.pdf
    • http://nakakinpump.kr/fckeditor/upload/file/mutudiwilosivopabisag.pdf
    • https://bibliotheque-des-arts.ch/ckfinder/userfiles/files/fasopodopofixusus.pdf
    • https://partner-support.net/user_data/userfiles/files/64801424657.pdf
    • http://bvsaigonbinhduong.vn/uploads/files/24325656874.pdf
    • https://asiabiru.com/contents//files/gisuviwizuzusefolu.pdf
    • http://budohurtsa.pl/userfiles/file/tuwanusalolusuxasox.pdf
    • https://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/v96nr14k4ef34bljspve9q37r4/63321286897.pdf
    • http://yuha.be/_files/file/39294128267.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e506.bin
ef34529ad882d2f73d426304600f5ec1695ab8297f0269e292374126b630b351
pdf-font-stream PDF embedded font (sfnt) at offset 0xE506 17684 bytes
font_01_sfnt_off00011376.bin
34837fdfed7e6dc9e8c1ebc45eabef1064a6e89f8cd536305124148a4af1fb29
pdf-font-stream PDF embedded font (sfnt) at offset 0x11376 16168 bytes
font_02_sfnt_off0001290d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1290D 16792 bytes
font_03_sfnt_off00014124.bin
cc4496086564af745f5c4708b40f522f03eca04b46362bd0b2abf3a164b852f9
pdf-font-stream PDF embedded font (sfnt) at offset 0x14124 10724 bytes