Malicious PDF — malware analysis report

Static analysis result for SHA-256 17ec201abb5318f1…

MALICIOUS

PDF

73.5 KB Created: 2021-09-06 11:29:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 0c41a33e54a4bf2b027ea326cd0f6bf0 SHA-1: 9ae7098ca739faaa76a35001268d917555da086d SHA-256: 17ec201abb5318f1de3ecb60d20f10c2a467aac5731a7283147e32271a8a5718
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external URIs and link farms pointing to potentially compromised websites or disposable hosting, indicating an attempt to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://synerhu.ru/uplcv?utm_term=heikin+ashi+patterns+pdf PDF link annotation
    • https://xn--fct5g39pjpo.tw/upload/leakstop/files/37273427253.pdfIn PDF document text
    • https://folklorebridge.eu/uploads/pictures/files/monumexutezedifugidogul.pdfIn PDF document text
    • https://x-software.cz/data/file/67078804397.pdfIn PDF document text
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b433fcc18dc---dawutosulomifemefevi.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b65d92b1866---81321255890.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dd5fc8c631a---19429180467.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/42cc1032a2391a5d7d1b3691f055f933/rabavebomeluv.pdfIn PDF document text
    • http://h-st.nl/bestanden/files/navubagorodufogozig.pdfIn PDF document text
    • http://topstec.com/d/files/54726628537.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/28c8b445e20cd539843f312ce1009905/24363865290.pdfIn PDF document text
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/16123484d55f9e---98718374401.pdfIn PDF document text
    • http://wedooverseas.com/userfiles/file/36450885666.pdfIn PDF document text
    • https://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/a1f4cb49af232bed2ab86bf52f2db3c5/devanimikavojavuzodu.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2c2088bcec---guduvanexenupuv.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077890eccc81---nefavurir.pdfIn PDF document text
    • https://digitaldaya.com/imagenes/file/fomifupi.pdfIn PDF document text
    • https://iaido-iaijutsu.ru/userfiles_exc/32122825121.pdfIn PDF document text
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079a30506b13---sedonumevomakopekibosulok.pdfIn PDF document text
    • http://chonburi33.com/userfiles/file/11613935446.pdfIn PDF document text
    • https://belgradenightlife.info/wp-content/plugins/super-forms/uploads/php/files/rgg77nvfmr4odqq53jbnabjrjn/wijodujorezevojufi.pdfIn PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/432a0bf971ffab1caf4260d4d0929cd5/modis.pdfIn PDF document text
    • https://uclerbaklava.com/resources/file/gavivotatolejevefenixap.pdfIn PDF document text
    • http://xboxheerlen.nl/userfiles/file/81800660529.pdfIn PDF document text
    • 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_off0000bdd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDD9 16468 bytes
SHA-256: 9ce6f426ab2df825d4122ca3f2771a46255eb0e6f2a64b288e7e75ee0124427a
font_01_sfnt_off0000e82e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE82E 10512 bytes
SHA-256: eb8cb5574ac735b3ebf22f69c4ee465e4f958d3cdda91fbbc8fb84d614538982
font_02_sfnt_off0000fffe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFFE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1