Malicious PDF — malware analysis report

Static analysis result for SHA-256 df0bf0e6165999b0…

MALICIOUS

PDF

109.8 KB Created: 2021-09-06 03:11:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 164dfa0b36ee16c4910c196e6ace1471 SHA-1: 627811dd3afb29fa84b6d37423963330b556599d SHA-256: df0bf0e6165999b0a31ee0c6e7dcce99abde3d7a539d82f8eabf29d4cf3fb16a
156 Risk Score

Malware Insights

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

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to redirect users to malicious content. The presence of numerous PDF links on disposable hosting further supports a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/eo3s4148jt0inv7gkpi97sctp6/41626313560.pdf In PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/a14i8mpc7tubeom3uo8j89g36e/30064375282.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/34227218010.pdfIn PDF document text
    • http://firmykominkowe.pl/Obrazki/edytor/file/duxubonuwamewat.pdfIn PDF document text
    • http://dlevitin.ru/fck_editor_files/files/78216483166.pdfIn PDF document text
    • https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d0f14d883f---78267081859.pdfIn PDF document text
    • https://etcbt.com/userfiles/file/43341679639.pdfIn PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/04gkllvr8dj3bfp1r7j64t7rp0/wofonenunulufosojeviw.pdfIn PDF document text
    • https://finliz.lt/i/File/tobumotawuvekikufajexer.pdfIn PDF document text
    • http://samtle.net/ckupload/files/87285990123.pdfIn PDF document text
    • https://samsungvrvklima.com/upload/ckfinder/files/9619389728.pdfIn PDF document text
    • http://aggengr.com/uploads/CMS/file/kopomumobimenu.pdfIn PDF document text
    • https://prtl.pl/userfiles/file/38687347925.pdfIn PDF document text
    • http://xn--k1akb4c.xn--p1ai/userfiles/file/zagopodar.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607e388a9bcb7---98113880893.pdfIn PDF document text
    • http://handsonmontessoripk.com/userfiles/files/xixewuf.pdfIn PDF document text
    • http://matsonconstruction.net/userfiles/file/39312250611.pdfIn PDF document text
    • https://nasikampung.info/contents//files/47894083891.pdfIn PDF document text
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/e8d14dfc7033ba97d20921a99e766d42/54287231761.pdfIn PDF document text
    • http://solemarservizi.it/userfiles/files/10593693953.pdfIn PDF document text
    • http://xn----otbbfbbknchz.xn--p1ai/sadm_files/21799557491.pdfIn PDF document text
    • http://archpiudue.com/userfiles/files/pikoranafosibukezuvofile.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=limits+at+infinity+worksheet+docPDF 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_off0001431d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1431D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00015b2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15B2F 20164 bytes
SHA-256: 0085d32733f41c583ccba6b8054b49e5aa1718bbd6dceffa28c4879e055d304d
font_02_sfnt_off0001905d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1905D 10944 bytes
SHA-256: d6ac0b297fca24c3645d673c4b66baaa60ef1fb03d98eac3ce32bc364aec78bb