Malicious PDF — malware analysis report

Static analysis result for SHA-256 71f98bd05e86b395…

MALICIOUS

PDF

88.6 KB Created: 2021-06-29 02:47:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c533442b1bae3ffaaed0db3d791d7c49 SHA-1: 609884fdb9179e44d65e193890762fecbd78b6d7 SHA-256: 71f98bd05e86b395825f4c6a7a996a7c6317dd73de3bacb49e1bf1c52f16b29a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains, suggesting a phishing or malware distribution scheme. The PDF structure and embedded URLs point towards an attempt to redirect users to malicious content, likely leveraging a spearphishing attachment vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://wastran.ru/uplcv?utm_term=92+resting+heart+rate
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089c6891e12f---fifikanuxuvu.pdf
    • http://jmdfhjl.com/fckeditor/userimages/file/gevolunojawotarotinumapog.pdf
    • https://activepymes.com/pub/file/xuwuwupulopuke.pdf
    • https://retta-bg.com/userfiles/nobagegiwareziv.pdf
    • http://rocincorporated.com/domain.com/images/dynamic_pages/file/rarefer.pdf
    • https://anmoul.com/userfiles/file/38036582589.pdf
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d35c74b8d79---titekosugojabez.pdf
    • http://www.asslar.de/downloads/27756806335.pdf
    • http://takemehometomatoes.com/ckfinder/userfiles/files/savozinusiworixojosi.pdf
    • https://shiokerbau1.com/contents//files/47102965418.pdf
    • https://universal4shipping.net/userfiles/file/34753608894.pdf
    • https://zebcom.in/userfiles/file/36949626148.pdf
    • http://www.klpreschool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a24b5f54f47---30793127470.pdf
    • http://bajcsidavidfoto.com/_user/file/95339116046.pdf
    • http://bawaconstructions.com/editorData/file/rujuxizab.pdf
    • http://businesslegalgroup.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/56690772539.pdf
    • https://navliecky.net/userfiles/file/18272020950.pdf
    • http://www.melloecastro.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073fd284dc84---13475877335.pdf
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/a9428b440a199d147cee705f4680aa4f/woguvifewijurededu.pdf
    • http://novichiha.ru/pic/file/10200237775.pdf
    • http://crmloccitanecr.com/campannas/file/satiguvamitobod.pdf
    • https://olterus.net/contents//files/zizoxefuvatevelosid.pdf
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/7458c9658cff0f8a13f3c8727e938d4b/13855040661.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_off0000f6e7.bin
d79d481d9d4acbff6f9f21a456ad36be610149e037de35a328a3230e29acd77a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF6E7 10412 bytes
font_01_sfnt_off00010e84.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E84 16792 bytes
font_02_sfnt_off00012696.bin
09ef19069664d1d44edc473e93567a9e01234318fa1b684799635041ce64f2ab
pdf-font-stream PDF embedded font (sfnt) at offset 0x12696 17336 bytes