Malicious PDF — malware analysis report

Static analysis result for SHA-256 37a21e5387f60124…

MALICIOUS

PDF

103.0 KB Created: 2021-03-14 13:02:15 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: 8a79e1961418031606e8bd422acd7604 SHA-1: b8f26f9aeb5de0cfc8d9910fdc502d151ea89b41 SHA-256: 37a21e5387f601242ff34f50ce37beaeddba71ef72f8605d5049280635fd6cd6
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to disposable domains or are used in a link farm configuration, indicating a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document designed to lure users to external sites.

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 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://vilenefex.ru/strik?utm_term=unity3d+asset+store+sale PDF link annotation
    • http://kefovatoxag.22web.org/mezesugigewim.pdfIn PDF document text
    • http://simcars.ru/pathfinder_cleric_feat_guide3gg4t.pdfIn PDF document text
    • http://leoidet.xyz/weider_pro_9940_home_gym_parts8f2qi.pdfIn PDF document text
    • https://birifebirox.weebly.com/uploads/1/3/3/9/133999865/regirepikag.pdfIn PDF document text
    • https://peliwotamo.weebly.com/uploads/1/3/5/3/135325711/tekozugibodi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371267/normal_604989542ec49.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4378161/normal_603fa026a2a01.pdfIn PDF document text
    • https://rixatesar.weebly.com/uploads/1/3/1/8/131871899/vimiz.pdfIn PDF document text
    • https://pegepigav.weebly.com/uploads/1/3/4/4/134481067/7a74bd5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393359/normal_60230f52af200.pdfIn PDF document text
    • http://likelid.xyz/biedermann_und_die_brandstifter_interpretationtcnzt.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://b2d1eea7-aef5-47fc-962c-88b5513ecafc.filesusr.com/ugd/3a57bc_4d79522b72ce49f8b5b269c7e952ddd3.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/e95a1f3a-2c60-4aae-bd9c-2810f8bb5c65/wolf_gourmet_countertop_oven_manual.pdfIn PDF document text
    • https://f8d4b294-f952-4a11-85e8-0a3036f9bdaf.filesusr.com/ugd/ad8f3a_838b4c7459b9474b88a5693a1b8db972.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/227051f7-6810-4750-bd56-301d081f7124/dukuxolasepuvefevum.pdfIn PDF document text
    • http://kapetevik.epizy.com/appium_android_test.pdfIn PDF document text
    • http://lisiguzaxupego.epizy.com/whiteboard_explainer_video_template.pdfIn PDF document text
    • https://cccd2283-d272-450a-840b-6541230ebad2.filesusr.com/ugd/5de1df_b0bea1f4e67f49b58045283e5ce613e2.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/5bcecabf-a624-4f1c-9db6-8b735c41534e/22523936559.pdfIn PDF document text
    • http://nejajubuwuwo.rf.gd/android_developer_tutorial_point.pdfIn PDF document text
    • https://5c2df1de-05ea-4e17-9aa3-38adc7ce3153.filesusr.com/ugd/ddd609_c7d73255fe764b7183bd08ff874f2976.pdf?index=trueIn 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_off000153a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x153A3 5076 bytes
SHA-256: 89f61440a67b8bb0df66483807b4ea1a1b07ee55668505dfac16c4bb018d4e89
font_01_sfnt_off000164fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x164FE 12092 bytes
SHA-256: 9666e7c6403f21891c7b3a6aab8f1420018e5a9be77ab402eff595659dd64965