Malicious PDF — malware analysis report

Static analysis result for SHA-256 43bc60b825dd3869…

MALICIOUS

PDF

74.5 KB Created: 2021-05-27 19:23:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 88a37c331691333a77f58c6e89b9390c SHA-1: 25be0ea72b92746a346430e9409d2144fb700d59 SHA-256: 43bc60b825dd38697e56d6a3fea67a08e955f86c0d1fc889ebc816a5351a9c1b
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, designed to mimic search results for free PDF downloads. The primary URL, https://ponafet.ru/strik?utm_term=pharmacotherapy+handbook+10th+edition+pdf+free+download, suggests a phishing or link farm tactic. ClamAV and ML classifiers also flagged this PDF as malicious, indicating a high likelihood of malicious intent, likely to redirect users to malicious content or download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.
  • 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://ponafet.ru/strik?utm_term=pharmacotherapy+handbook+10th+edition+pdf+free+download PDF link annotation
    • https://lijupumo.weebly.com/uploads/1/3/4/4/134496400/redejijimuvoze_botatorabexege.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477638/normal_6044dc5846b78.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4368251/normal_5fcedd3423dff.pdfIn PDF document text
    • https://noratelesuvefo.weebly.com/uploads/1/3/7/5/137505873/4256794.pdfIn PDF document text
    • https://xipurewaxo.weebly.com/uploads/1/3/4/7/134759043/3316105.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4493876/normal_5ff0c9453da89.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4411686/normal_60570c1d7a648.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4489595/normal_5ffc10755aaae.pdfIn PDF document text
    • https://saposoralax.weebly.com/uploads/1/3/6/0/136025319/9501677.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375891/normal_6043395c6d14d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451221/normal_5fdba88138ae2.pdfIn PDF document text
    • https://zedodunojoponex.weebly.com/uploads/1/3/6/0/136083391/wowupurez_kolizugir.pdfIn PDF document text
    • https://ledunadexaw.weebly.com/uploads/1/3/0/7/130775166/9ec9cf762a3c99e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366312/normal_60437c8ccf34a.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/a31e08ad-b574-40b5-8e9a-4bda433abef1/15123251691.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bfa2cedf-3511-493a-b66c-12ae238bf129/life_in_the_trenches_ww1_worksheet_answers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/67d7bfbb-3468-4371-b0e1-9624bbb6594b/dell_optiplex_7010_motherboard_form_factor.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d6b2673f-169d-4b04-b39d-607f18bcb150/what_killed_the_andromeda_strain.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b6f5e656-ced4-44bb-856d-cdc54193c389/tilirovogibafuwozevakabi.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_off0000e3a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3A7 5808 bytes
SHA-256: a2274de02a891f9231f7851355088a8f77a40666961aa5877df05c7fe3b0e0a4
font_01_sfnt_off0000f75f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF75F 10892 bytes
SHA-256: 5711a98b8f6af30d2207359aa6b6b1f6da8d9a0fd025a6d6f5211e30cce40739