Malicious PDF — malware analysis report

Static analysis result for SHA-256 a528aaef05327829…

MALICIOUS

PDF

72.2 KB Created: 2021-06-09 13:56:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 279c93216824214ccf4b33b5898140ae SHA-1: addce3f8372729a37d1617c86182d916747b14bd SHA-256: a528aaef05327829766ffd87c263a794e0704598d5b3b1fb01bc4144cf8d7aa3
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 pointing to disposable hosting, indicating a link farm or SEO spam operation. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution via these links. No scripts were extracted, but the PDF structure itself is used to host and redirect to numerous external URLs.

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://pixomot.ru/pbw?utm_term=complementary+supplementary+angles+worksheet PDF link annotation
    • https://nakebakij.weebly.com/uploads/1/3/5/3/135339599/jujuzorubanuzuw.pdfIn PDF document text
    • https://tofesozexeraj.weebly.com/uploads/1/3/4/6/134610570/6faf9a.pdfIn PDF document text
    • https://jirakevajiw.weebly.com/uploads/1/3/5/9/135966085/e7df3be82b5b6.pdfIn PDF document text
    • https://xugowumilivave.weebly.com/uploads/1/3/4/8/134846580/3925200.pdfIn PDF document text
    • https://finirawex.weebly.com/uploads/1/3/2/7/132741073/2326620.pdfIn PDF document text
    • https://removevas.weebly.com/uploads/1/3/4/4/134443453/petijewuxajukid.pdfIn PDF document text
    • https://tefimapotile.weebly.com/uploads/1/3/4/3/134351392/1604726.pdfIn PDF document text
    • https://kilifunilazavef.weebly.com/uploads/1/3/4/4/134481566/1944415.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://dipoziw.pbworks.com/f/what_are_upper_and_lower_bounds_in_calculus.pdfIn PDF document text
    • http://ririgifavem.pbworks.com/f/vce_to_converter_online_tool_free.pdfIn PDF document text
    • http://lomubel.pbworks.com/f/tom_and_jerry_the_midnight_snack_1941.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a05b657e-08ee-47fb-ac1e-b74d4a04357b/subeloxozovatax.pdfIn PDF document text
    • http://safopiluzaw.pbworks.com/w/file/fetch/144941661/bloons_td_6_free_android_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c64e29fc-fc4e-4804-9225-42a7bf3026bc/liftmaster_8500_light_not_working.pdfIn PDF document text
    • http://lomexalipele.pbworks.com/w/file/fetch/144514716/65959891138.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c2a501e5-8dc9-4dfe-9def-e4f0f89a1b4c/nezigujubulegu.pdfIn PDF document text
    • http://fibonilavi.pbworks.com/w/file/fetch/144934068/pixel_art_studio_tutorial.pdfIn PDF document text
    • http://nuxawakaxaz.pbworks.com/w/file/fetch/144922566/biology_class_12th_book.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ee28e4f0-9257-4de1-8f3f-e5e74564339b/how_to_convert_whatsapp_audio_opus_to_mp3.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/468bdd76-e16c-4371-b369-c0f4ed69a577/61490777134.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b4b770a4-e650-42b7-a9cd-eecc7d86e319/paniwokawasolawedatogexiw.pdfIn PDF document text
    • http://lomexalipele.pbworks.com/w/file/fetch/144515412/counter_strike_1.3_free_download_with_crack.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_off0000db56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB56 5396 bytes
SHA-256: f94d250f98036ea5b1f3b2c8a1f338097e857fef83f2a893139c4a2af55bd6cd
font_01_sfnt_off0000ed9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED9B 10908 bytes
SHA-256: 7ad6fdb75ef9d1a211abb5df8bb5086d82e201837a59923afebc83e5cf5e85f2