Malicious PDF — malware analysis report

Static analysis result for SHA-256 df4b90da92fd7381…

MALICIOUS

PDF

86.5 KB Created: 2021-07-13 01:09:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e540069e8643259fd647b6f7d1ef4d53 SHA-1: 50ee7d64052b32521a4327005ebcd2ee1901e54d SHA-256: df4b90da92fd738142181a922b6b0d9741c26ed0d94cb52103b06c4ac832040b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm with numerous URLs pointing to compromised WordPress upload directories, suggesting an attempt to host malicious content or redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the presence of multiple suspicious URLs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic point towards a phishing or scam campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e1d51ed0a8---xoletejirusunawuz.pdf
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/fb352a0cd36cee8916fb64ceb561fb56/6844495533.pdf
    • http://garderoba.sk/images/_file/35120123577.pdf
    • http://zxsolar.com/d/files/voxazeziboz.pdf
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/h7ijeh6besvtvm3c88n7h8ljo1/70932230088.pdf
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/e0eb51f66dfb074ef5fb11c62d499ed3/zexelogumefokuvatovifidaw.pdf
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0b9efd44a0---fawowigotuwurado.pdf
    • http://cameradungphat.com/uploads/files/77336239440.pdf
    • http://mfcwestenkwartier.nl/beta/userfiles/file/23105568202.pdf
    • http://vankouwenenmastop.nl/UserFiles/file/28013855427.pdf
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1606f188eb775a---watujobulitudalunemajal.pdf
    • https://hasekei.jp/userfiles/file/25271581806.pdf
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/44eec7b3e29e6c5e5dc89cf4f3bd1e7c/dasefuf.pdf
    • http://csc-020.com/userfiles/file/20210623075232_0xfz6v.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160792f70b432c---xipebigabuzekosanevoki.pdf
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/9dn7rea1eap5hqmv2pfmjqga0j/mefutokowafubasubapo.pdf
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609b9bd3ab5d6---xazirarofuwud.pdf
    • https://prawobrzeze.info/userfiles/file/gubupewe.pdf
    • http://falerisztika.hu/tmp/47228462605.pdf
    • http://parejalecaros.com/adjunto/upload/fck/files/taxegobojopegulogur.pdf
    • http://stin-verdon.fr/assets/Image//files/1232573723.pdf
    • http://stressmanagement-karriere.de/userfiles/file/vetogumumijozipubodog.pdf
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fee05be38f---karaf.pdf
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/96cdb9bd7c70c8c6dbb025cfcf33afc6/79393222737.pdf
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609f280fb323b---tewavanuroxumuvexavaxesa.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=best+business+during+recession
    • 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_off0000eefd.bin
643e02a09f5755a6819cd258b122fd0d2581719ef3ea408a45cfe3cd51306368
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEFD 10628 bytes
font_01_sfnt_off00010739.bin
605f839c7243ee20631842b5eaf077a45a37b887f453a1e8aa945eeacfe6f186
pdf-font-stream PDF embedded font (sfnt) at offset 0x10739 17284 bytes
font_02_sfnt_off00013470.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13470 16792 bytes