Malicious PDF — malware analysis report

Static analysis result for SHA-256 a84770b2fcca91e4…

MALICIOUS

PDF

71.5 KB Created: 2021-09-16 12:08:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: c3eb3e7e09e83450c17572bff1d180b4 SHA-1: 9858b26bf6612b25a8c9cd32bc521797e3eacd7f SHA-256: a84770b2fcca91e4fd13b3a28bc62c04631ebe0dd0037aaa267961398cbe63b6
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. Several heuristics indicate the PDF acts as a link farm, pointing to multiple distinct hosts, some of which are compromised WordPress upload directories. The embedded URLs suggest an attempt to direct users to potentially malicious content, aligning with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://gz-chengeng.com/uploadfile/files/liwame.pdf In PDF document text
    • http://alexlunacoach.com/img/editor/file/85455725664.pdfIn PDF document text
    • http://playoz.com/ckfinder/userfiles/files/faresi.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fea7b5c78a---11747357292.pdfIn PDF document text
    • https://eric-parnes.shortex.com/ckfinder/userfiles/files/1146424765.pdfIn PDF document text
    • http://mexvp.com/ckfinder/userfiles/files/61879630178.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/f3462ce1b6f6402754f40fc012209ed4/widur.pdfIn PDF document text
    • http://gibisch.org/files/files/38685712192.pdfIn PDF document text
    • http://gabident.pl/local/userfiles/file/29666812144.pdfIn PDF document text
    • https://mi-stores.com/basketballtotaal/images/editor/file/zulimawagukova.pdfIn PDF document text
    • http://nhakhoauytinhaiphong.com/upload/files/namosadazonudamufomoriz.pdfIn PDF document text
    • http://www.sczct.com/up_files/file/menakebiwifiwida.pdfIn PDF document text
    • http://hatdesechia.com/storage/ckfinder/files/revubitelaregenoseponukev.pdfIn PDF document text
    • https://ddtoyz.com/ckfinder/userfiles/files/savigukenikifege.pdfIn PDF document text
    • http://abnicum.ru/files/file/93355076943.pdfIn PDF document text
    • http://innova-perila.ru/upload/files/pakokividonadexodom.pdfIn PDF document text
    • http://odra.cycling-recycling.eu/imgturysta/files/16717065444.pdfIn PDF document text
    • http://alacarte-husum.de/userfiles/file/35213670496.pdfIn PDF document text
    • http://firsttimehomebuyerstudy.com/images/file/59381220200.pdfIn PDF document text
    • http://hoangnampte.vn/quangbasanpham/app/webroot/upload/image/files/zifogimebafox.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/16141ae4a1b30d---subizumolo.pdfIn PDF document text
    • http://2478.ru/admin/ckfinder/userfiles/files/birajotoraboli.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=android+auto+clonePDF 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_off0000b687.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB687 16444 bytes
SHA-256: bad74cf1a64217697772dc8ce0165e2d92142ccdb75ab38798949f7bcc585ad3
font_01_sfnt_off0000e11e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE11E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f935.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF935 10276 bytes
SHA-256: bb1f65da9046cbd92c7713d221ce4fffb60e385e82539d2cabd60d83d297d538