Malicious PDF — malware analysis report

Static analysis result for SHA-256 3179a92c779795c9…

MALICIOUS

PDF

73.7 KB Created: 2021-02-06 18:46:23 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 90dc8e71dd4056a9ab2eb393e18fd4b5 SHA-1: e887c0d035e0b3b08ae066b0486f64bca5ea0333 SHA-256: 3179a92c779795c932b96556ed50f91f50b0a29575b4358706ff9f128caed91a
204 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many of which are part of an SEO link farm designed to redirect users to potentially malicious content. The primary redirector URL is 'https://seumenha.ru/aws?utm_term=alphabet+tracing+printable+worksheets', which is presented as a source for free downloads. ClamAV detected this file as 'Pdf.Phishing.Trojan-d2528dad23a95d95-10044376-0', and an ML classifier also flagged it as highly malicious. No scripts were extracted, but the PDF structure and linked URLs indicate a phishing and potential malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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/aws?utm_term=alphabet+tracing+printable+worksheets PDF link annotation
    • https://tuboxivodase.weebly.com/uploads/1/3/4/3/134387713/towusugot.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4420905/normal_6007d24b2c09b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4385617/normal_5feb725903ba8.pdfIn PDF document text
    • https://nonewogigej.weebly.com/uploads/1/3/2/6/132681399/91ac63b90eb.pdfIn PDF document text
    • https://cdn.sqhk.co/tibakekavero/iiVnLOV/92436152392.pdfIn PDF document text
    • https://wotigutaz.weebly.com/uploads/1/3/4/3/134361511/0a4f1350.pdfIn PDF document text
    • https://cdn.sqhk.co/fevivesuxofo/jdgh2gg/pinout_rj45_poe.pdfIn PDF document text
    • https://latitatuforuza.weebly.com/uploads/1/3/1/3/131398212/jitezigimotira_wofoxodina_mamefujezejure_sinewulubi.pdfIn PDF document text
    • https://ripukalogud.weebly.com/uploads/1/3/4/3/134391837/faxosevetutitop_xukagugevolode.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://s3.amazonaws.com/fokapikow/november_2018_calendar_printable_template.pdfIn PDF document text
    • https://s3.amazonaws.com/nuxulikiwab/bound_by_flame_trainer.pdfIn PDF document text
    • https://s3.amazonaws.com/negonanopix/64051139143.pdfIn PDF document text
    • https://s3.amazonaws.com/pogolo/kritika_the_white_knights_eclair_guide.pdfIn PDF document text
    • https://s3.amazonaws.com/levumoduf/bahubali_songs_free_starmusiq.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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d544.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD544 5268 bytes
SHA-256: aa8a6927dce3dabfbca0483345ac514ebddc69ef666405ab6a2790d8fd24e35a
font_01_sfnt_off0000e722.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE722 10684 bytes
SHA-256: 220fb5f0a7199fb6aeb21de4923bde009cdea06e310d050a1886c3e4e06ed340
font_02_sfnt_off00010b90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B90 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34