Malicious PDF — malware analysis report

Static analysis result for SHA-256 f451fb5e6b3f550a…

MALICIOUS

PDF

85.1 KB Created: 2021-09-05 04:25:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 599330f79bf5f453661dac6cdd252d99 SHA-1: 0c8ee9670f0ef2c738dea738a36be10bf9f4802a SHA-256: f451fb5e6b3f550a67cb3107f7cbcfed16a04b1696275a4c0262499d2596cebc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains numerous embedded URLs pointing to various domains, many of which appear to be compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a non-clustered link farm on disposable hosting, reinforcing the phishing or malware distribution intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://ketchas.ru/uplcv?utm_term=epiphyllum+phyllanthus+pdf
    • https://aimhc.com/userfiles/file/38378101591.pdf
    • http://partner-support.net/user_data/userfiles/files/womoki.pdf
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e336769777---vikezema.pdf
    • http://www.propper-droppers.nl/files/file/duloburedo.pdf
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/16094d8c1e040b---punexarujokaponareg.pdf
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085205693469---wozumovulij.pdf
    • http://dharmapuridiocese.com/svnprojects/DHD/Source/images/files/xigituxeluro.pdf
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/1608ff255c5917---40446931302.pdf
    • http://bekescsaba.varosom.hu/userfiles/files/xokabaxe.pdf
    • http://wdnederland.nl/file/kazapo.pdf
    • https://biothiennam.com/media/ftp/file/wonatosew.pdf
    • https://www.cibaospalaser.com/wp-content/plugins/super-forms/uploads/php/files/hgjrcjbue35d5b2um5im3fv502/gesuzetubazonu.pdf
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080d267a89f0---89272699437.pdf
    • http://cherryontop.pl/upload/fotki/file/31450072337.pdf
    • http://tourister.kr/userfiles/file/jijug.pdf
    • https://morabia.fi/images/file/32692232431.pdf
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/2f33eb7f16ac42bbaf24043e3790d51b/62533783163.pdf
    • http://ahxxzx.com/userfiles/202105/file/30341831317.pdf
    • http://location-appartement-venise.com/italie_documents/files/zazikatexo.pdf
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098475e0bf9e---78298338008.pdf
    • http://ilovemynewstemcells.com/clients/865932/File/tofonutugitibivape.pdf
    • http://hide-bo.com/img/tmp/file/wokuzabemojenapisirare.pdf
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/u8f93ovgvdeou3bqvqdhu23dd7/dipugefudufamudajidolevak.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_off0000e63f.bin
c9a3e971f9357c074379cf197f27dc05abcfc915fb8ac149c8fbedd16591dd8b
pdf-font-stream PDF embedded font (sfnt) at offset 0xE63F 10608 bytes
font_01_sfnt_off0000fe40.bin
938acf2c3d8d3ce0a0ea8be99dae9558b70c941456507b4aadfd62a6651afbaa
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE40 18704 bytes
font_02_sfnt_off00012f18.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F18 16792 bytes