Malicious PDF — malware analysis report

Static analysis result for SHA-256 0833f3dcd03b23fe…

MALICIOUS

PDF

74.7 KB Created: 2021-09-02 02:08:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 40601811efdf19fe3a2221a0ff0e65ff SHA-1: f227b78f8bdc8adef8811ca82b10c7d0f6129343 SHA-256: 0833f3dcd03b23fe4b844b9f21640f8fd82ce1f35e11de0069984da0ebcc775c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a link farm with numerous URLs pointing to various websites, many of which are hosted on compromised CMS platforms or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded URLs and the nature of the link farm suggest an attempt to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://okmarin.ru/userfiles/file/korakazo.pdf
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/3e947e14c3afb6b26fbae69b4ef9d0f1/63487395398.pdf
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/160cfc87489aef---26462525228.pdf
    • https://bostoncake888.com/UserFiles/files/37693722617.pdf
    • http://wignaccent.com/FCKeditor_2.6.3/userimages/file/20210801003258.pdf
    • http://residencelesaline.it/userfiles/files/wukib.pdf
    • https://chiuman-hk.com/images/file/27438905842.pdf
    • http://woodwork.pl/ubezpiecz/obrazy/file/zizamekibobene.pdf
    • http://thetuckerfamilyreunion.com/clients/67950/File/69904584384.pdf
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/uuuso5mjtt14t2ro8gh2l4dfhi/16506723919.pdf
    • http://vaynhe.com/upload/files/rikakanobuwosabi.pdf
    • https://anitacalderon.com/ckfinder/userfiles/files/selisulabevevepisiwofide.pdf
    • http://mos-craciun-inchiriere.ro/fckfiles/file/11935570820.pdf
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c1cbbf69b64---31498305548.pdf
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f7223e2249---85059023715.pdf
    • http://suvagcentr.ru/userfiles/files/818099825.pdf
    • http://studiorapizza.it/userfiles/files/94176723520.pdf
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607631ae75e9f---28122271901.pdf
    • https://eternalbliss.net/file/revironajo.pdf
    • https://coil.hk/upload/files/sotebabob.pdf
    • http://fitviewer.biz/files/file/79488360251.pdf
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1251dc537---5549662494.pdf
    • http://slsnn.ru/content/file/97220322351.pdf
    • https://mintedimages.com/ckfinder/userfiles/files/26304123520.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+create+3d+pdf+from+solidworks
    • 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_off0000bfe0.bin
7785fdce880b2ecf39dde0cd9d0803c8a1ce70c18e4b232ddf8e5ac0c3b0e8ec
pdf-font-stream PDF embedded font (sfnt) at offset 0xBFE0 16964 bytes
font_01_sfnt_off0000ebce.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEBCE 16792 bytes
font_02_sfnt_off000103e5.bin
e7296308a6d73e332965486b0ecce956c7c776d4e1fa312ef4728957b4d208dc
pdf-font-stream PDF embedded font (sfnt) at offset 0x103E5 11016 bytes