Malicious PDF — malware analysis report

Static analysis result for SHA-256 de626c74dee56fb8…

MALICIOUS

PDF

123.4 KB Created: 2021-09-09 22:26:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 6b8ca7a795690bac323e435e6a88e787 SHA-1: 70ddffaec751ae687fa9959db9e8d94860264be4 SHA-256: de626c74dee56fb86d4714b5859943abc98a3ebac0f1a42ed9e3ed595d14bd10
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and contains embedded JavaScript. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9927

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1612f11425cb3c---nituweze.pdf In PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f5a985b61d---tevuvutixakevaselete.pdfIn PDF document text
    • http://ikuma-car.com/js/upload/files/romozevuzu.pdfIn PDF document text
    • https://yesilkoyluleriz.biz/resimler/files/70962134518.pdfIn PDF document text
    • https://slezanie.eu/userfiles/file/77673466608.pdfIn PDF document text
    • https://termoformat.md/img/files/pidedabunebiwajeno.pdfIn PDF document text
    • http://pokorny-podlahy.cz/UserFiles/File/29460333769.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/f81a17030d240a2a84dd8f48254d5264/suwajomugedinolope.pdfIn PDF document text
    • https://www.libyamonitor.com/sites/all/libraries/ckfinder/userfiles/files/77439688870.pdfIn PDF document text
    • http://pibar.tw/uploads/files/202109050018284148.pdfIn PDF document text
    • http://brickform.cz/obrazky/files/mepimipixa.pdfIn PDF document text
    • https://webvitamin.vn/app/webroot/uploads/files/32512070767.pdfIn PDF document text
    • http://thoitrangvabaoho.com/Images_upload/files/92408465423.pdfIn PDF document text
    • http://talesma.com/E/file/83595211849.pdfIn PDF document text
    • http://eternaseguros.net/files/files/54408009529.pdfIn PDF document text
    • http://mentor-tutor.com/newGroserLikeProject/uploads/files/bujer.pdfIn PDF document text
    • http://asdgolfclubtoscana.com/writable/public/userfiles/file/fepamoluxabadak.pdfIn PDF document text
    • http://jucal.es/images/file/vuxuwapinona.pdfIn PDF document text
    • http://slovbau.sk/test/userfiles/file/61900019675.pdfIn PDF document text
    • http://bzws.zhanyougame.com/ckfinder/userfiles/files/dinegavawizelopotekitar.pdfIn PDF document text
    • https://verner.lt/images/files/19228670970.pdfIn PDF document text
    • http://a1climbing.com/userfiles/files/baluxizix.pdfIn PDF document text
    • https://zagorjeadventureteam.hr/files/92218030050.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=aktualizacja+androida+samsungPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00015ff4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15FF4 16952 bytes
SHA-256: 23e8ea86a6cce00726351ac355fecf2a291e7d985e246c7cc3afb63fd6bc33e4
font_01_sfnt_off00017874.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17874 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001908b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1908B 10944 bytes
SHA-256: 49d29fcef6274fe49b3d26529e558324339835720e79de6527c488f4b1b05af4
font_03_sfnt_off0001a9b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A9B1 21740 bytes
SHA-256: 32274690b1c7e51419a980486d761852173063f4e1fcb8630d9a43d37562b347