Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf5a99bca5b3ff69…

MALICIOUS

PDF

98.1 KB Created: 2021-02-16 04:44:43 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: a2f75139a46fc17ed1af3c629d08bc8e SHA-1: 1efab068cbf62f76406429b09e70b535edcce5ba SHA-256: cf5a99bca5b3ff69a2f1f045eff66f30e468988d26b44454a761f242d01e8b07
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains multiple heuristics indicating it is a link farm designed to host malicious content, with one URL specifically identified as a potential phishing or malware distribution point. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a phishing or malware delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://seumenha.ru/strik?utm_term=basic+mathematics+formula+for+competitive+exams+pdf PDF link annotation
    • http://aycotoro7.xyz/how_to_gift_shark_cards_on_xbox_ones36ov.pdfIn PDF document text
    • http://tiwirodizefa.iblogger.org/postnatal_depression_assessment_form.pdfIn PDF document text
    • https://cdn.sqhk.co/juzureniwibu/0ib5Thh/cima_study_text_e3_strategic_management.pdfIn PDF document text
    • https://cdn.sqhk.co/sowojusawepu/FhgTZ31/duvojekupo.pdfIn PDF document text
    • http://mumokajepuxu.iblogger.org/crystal_reports_for_visual_studio_2008_tutorial.pdfIn PDF document text
    • https://gapemudumowew.weebly.com/uploads/1/3/1/4/131437765/zojaw.pdfIn PDF document text
    • http://zaxunux.iblogger.org/givede.pdfIn PDF document text
    • https://gutoxokotuvil.weebly.com/uploads/1/3/1/3/131380594/kozewofekok.pdfIn PDF document text
    • https://nosodelutota.weebly.com/uploads/1/3/1/8/131857544/wubovadexiravi.pdfIn PDF document text
    • https://cdn.sqhk.co/novitovikor/Ijiachh/recargas_claro_ecuador_promociones.pdfIn PDF document text
    • http://idealslimitaly.site/boxawovefalojol17i8.pdfIn PDF document text
    • https://razamilijukiw.weebly.com/uploads/1/3/4/8/134879964/954490.pdfIn PDF document text
    • http://brumbum2.xyz/glitz_formal_dress_boutique_houston712i2.pdfIn PDF document text
    • https://cdn.sqhk.co/mitukutowum/fGYighg/vuketigufu.pdfIn PDF document text
    • https://dafufiwe.weebly.com/uploads/1/3/4/3/134368649/wokototepagamosud.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fedorahosted.org/lohitIn PDF document text
    • https://s3.amazonaws.com/likerajatob/ameritas_dental_enrollment_form.pdfIn PDF document text
    • https://s3.amazonaws.com/liwafo/camera_icon_missing_on_android_phone.pdfIn PDF document text
    • http://numowun.rf.gd/peppa_pig_coloring_sheets.pdfIn PDF document text
    • http://supewomok.epizy.com/5th_grade_math_addition_worksheets_printable.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://scripts.sil.org/OFLIn 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_off00011774.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11774 5572 bytes
SHA-256: 13b1d7d062be2761757dcc84e97c15c198ad91ce9f0e9ad2db1ca8b18fcd9104
font_01_sfnt_off00012a45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A45 13236 bytes
SHA-256: 7ba5b34c631e16e1eb0f45321a5390466c76257f6a947b347d5551b0308a1c2f
font_02_sfnt_off000156e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x156E9 16252 bytes
SHA-256: 12e04400172eba6ce5992ab30981ecec38e948f549fd213114791712f0ae7bc2
font_03_sfnt_off00016c9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16C9C 3352 bytes
SHA-256: 481c01aab70e647bc96ba4707f077a20a60e6dcb3e7add9d235f0393edcd9c2f