Malicious PDF — malware analysis report

Static analysis result for SHA-256 d47928cafbf38e61…

MALICIOUS

PDF

75.8 KB Created: 2021-05-01 05:25:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 1bfb09586dc3323221768d6d85e178f2 SHA-1: c48c79d1dd185ed989eca5d5a0843e981376eede SHA-256: d47928cafbf38e619edb174bc59c68cec75c439b3309d4cc2eee8e672be1c6ae
196 Risk Score

Malware Insights

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

The PDF contains a high number of external links, many of which are SEO-optimized and lead to redirectors, indicating a link farm or phishing attempt. One prominent URL, 'https://jacksth.ru/strik?utm_term=public+health+administration+jobs+in+atlanta+ga', is presented as a lure for job seekers. ClamAV and ML classifiers also flagged this PDF as malicious, specifically as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 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.
  • 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://jacksth.ru/strik?utm_term=public+health+administration+jobs+in+atlanta+ga PDF link annotation
    • https://rajexomogalifi.weebly.com/uploads/1/3/4/8/134891851/93434c8c.pdfIn PDF document text
    • https://cdn.sqhk.co/sobilowibid/uNjfhax/70153106518.pdfIn PDF document text
    • https://xebazasasixuj.weebly.com/uploads/1/3/4/6/134641459/8021749.pdfIn PDF document text
    • https://tipureroxagojox.weebly.com/uploads/1/3/6/0/136096040/kokoloj-dixokukumapu.pdfIn PDF document text
    • https://cdn.sqhk.co/dufikibagi/7nbieDy/bipekutinaxapotuxemiragel.pdfIn PDF document text
    • https://cdn.sqhk.co/gabebutiz/ehn6Ugf/92550197945.pdfIn PDF document text
    • http://kutakelipaxeb.22web.org/fejupelisifuf.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/lomiwexuva/toyota_car_radio_stereo_audio_wiring_diagram.pdfIn PDF document text
    • https://f421159b-d329-41e8-bc42-072bc93e4c50.filesusr.com/ugd/65d6f7_23f423ed5aa54ff0a69a2aa709cb488d.pdf?index=trueIn PDF document text
    • http://demunoj.epizy.com/answered_meaning_in_bengali.pdfIn PDF document text
    • https://0ac950e2-707a-4e47-8bf4-daface0ea9db.filesusr.com/ugd/356f11_49c02fc2f9264e58aeb88fb115180635.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/ronenitevodo/97505348993.pdfIn PDF document text
    • https://s3.amazonaws.com/fowikorejodi/doubling_and_halving_year_3_worksheets.pdfIn PDF document text
    • http://donuvegiwezef.rf.gd/blade_s_guide_to_making_knives_2nd_edition.pdfIn PDF document text
    • https://s3.amazonaws.com/gozifep/matthew_henry_prayer_of_thanksgiving.pdfIn PDF document text
    • https://fb5b3b17-6e6a-47c5-ae49-26eddba71e57.filesusr.com/ugd/aff7be_d6c5c78bf6834bdf8e98637cd0d1e17f.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/luxaduzimase/bhojpuri_film_video_songs_free.pdfIn PDF document text
    • https://s3.amazonaws.com/farowug/what_is_the_bar_professional_training_course.pdfIn PDF document text
    • http://sanaxumidi.epizy.com/felowiduvomozugiba.pdfIn PDF document text
    • https://06ebba1c-c738-45d4-b58d-83edbdcc9420.filesusr.com/ugd/b14caa_3fb33c5b97464cfbb055e2f3b1bc76b4.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/muwemivumazulax/australian_humanitarian_visa_form_681.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e892.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE892 5568 bytes
SHA-256: 6a95c3bcd550f704033d86bbda0734f32b4b5d8c201e01fdb124a6ac82e6ac6d
font_01_sfnt_off0000fb51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB51 11576 bytes
SHA-256: 349ce687d6134237ba4fde86249d5d33b9cc03b5815648fb36efdffa1ab91ca2