Malicious PDF — malware analysis report

Static analysis result for SHA-256 13f834ec36bcb6c4…

MALICIOUS

PDF

86.7 KB Created: 2021-07-18 14:15:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 6235fbc8625a79a1e3a7a3d6aa745e98 SHA-1: 5e91b32fe9ae4a712d2e114f2fda7f0d6f0ee394 SHA-256: 13f834ec36bcb6c4132c5d8b75468658aa46f08527905cf8567b5a0115aae446
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1055.012 Process Injection

The PDF contains numerous links pointing to compromised WordPress sites, indicating a link farm designed to obscure the ultimate destination. ClamAV and ML classifiers strongly indicate maliciousness, specifically classifying it as a phishing trojan. The presence of multiple distinct hosts and a high number of links suggests an attempt to distribute malicious content or phishing lures through a compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

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.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/160738ed2eea50---jeniverafefegafefoteba.pdf In PDF document text
    • http://podlahypilat.cz/admin/file/xipunefufoparilaxevudadet.pdfIn PDF document text
    • http://naplesredeals.com/userfiles/files/metux.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160856b60f191e---rejorewaderejorobitu.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073be58c7d56---didemuk.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/160af86888df56---81593890433.pdfIn PDF document text
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609faf389de59---20719330535.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/48f62f3f531c362d84120d15eb489238/kiroxozagaxunoritofariji.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/160901462c3fca---nodubowizupodavif.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/1c7125f744d3c4155f9e332773977579/74404075859.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/rgfp5gnpu95qikflmo8jt4671h/gusamafufizila.pdfIn PDF document text
    • https://spectrumohio.com/wp-content/plugins/super-forms/uploads/php/files/044d3253eef9ac06844435cdbd996204/koveximananobujatov.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/rpbpaksk1cgeu3q96begd2uca4/23165661278.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/a04d109a1c54b891b4d60e4edcb2f066/wofuw.pdfIn PDF document text
    • http://project-lovcen.me/userfiles/file/gosimufejejimomajifix.pdfIn PDF document text
    • https://vidolamerica.org/wp-content/plugins/super-forms/uploads/php/files/5e495d1455d85be945ae09a0f5d33d3d/fodepevesunufokuw.pdfIn PDF document text
    • https://theatresaucinema.fr/uploads/file/72896501277.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/1608dcda072183---rewinomekenozodazeva.pdfIn PDF document text
    • https://skatrip.com/basefile/skatripcom/files/46517724615.pdfIn PDF document text
    • https://plagij.at/ckfinder/userfiles/files/85426238935.pdfIn PDF document text
    • https://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/aaa6efa053a51d891f326bb467371344/26677197719.pdfIn PDF document text
    • https://cvzona.lt/resources/img/files/87150376750.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f60bd10398---zinukilazetogibugomezo.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/5d1582d48818bc366e354833ae9c5eaa/67978075473.pdfIn PDF document text
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/9p9gg5d4j98c5reu926uksqra1/wuruki.pdfIn PDF document text
    • http://ndt-tl.ru/upload/file/kulatex.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=beaver+brothers+tree+servicePDF link annotation
    • 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_off0000efe1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFE1 10436 bytes
SHA-256: 026c7358ba7a5ff74e9e71218545dc11f79d9cbc7c923e2edb6871f282a3d0f0
font_01_sfnt_off000107c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011fdb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FDB 17420 bytes
SHA-256: 4c2008acb039f50456f269278d7a0dbae97321898062231e4a4c542369afbe49