Malicious PDF — malware analysis report

Static analysis result for SHA-256 b21626535c6fdcf1…

MALICIOUS

PDF

72.0 KB Created: 2021-05-11 10:05:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c025cbf2c15e72bab21d6d7b42d49543 SHA-1: 21628d40d409d70b39ed5ea565bd53f3083b4f86 SHA-256: b21626535c6fdcf13201c81efeab54dbc412ff1941962d05fa467eeeab66f192
96 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains an embedded URI pointing to 'nipisod.ru', which is likely a phishing lure. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the detection suggest it's designed to redirect users to malicious content, potentially for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 4

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://nipisod.ru/strik?utm_term=how+to+say+tempus+fugit
    • https://cdn.sqhk.co/rijomawonuj/bgjidjb/81040388904.pdf
    • https://cdn.sqhk.co/latusetime/5MXhdih/vast_tv_everywhere.pdf
    • https://cdn.sqhk.co/parabeset/r99gchg/9877188370.pdf
    • https://sakixuso.weebly.com/uploads/1/3/4/4/134488330/4062745.pdf
    • https://cdn.sqhk.co/nupasoxure/6RO3r20/nails_for_you_2.pdf
    • https://static.s123-cdn-static.com/uploads/4481513/normal_5fdfb1c4cb897.pdf
    • https://cdn.sqhk.co/tosijoxopum/ZjdZhxC/80s_songs_hits_list.pdf
    • https://cdn-cms.f-static.net/uploads/4420592/normal_601ae036d5950.pdf
    • https://cdn.sqhk.co/netimawifes/fjggdih/85686779536.pdf
    • https://cdn-cms.f-static.net/uploads/4460048/normal_601b38fe4d1c9.pdf
    • https://gudemulu.weebly.com/uploads/1/3/4/3/134387893/b10c82fd86.pdf
    • http://monubagujizud.mywebcommunity.org/dunkin_donuts_cinnamon_coffee_roll_k_cups_calories.pdf
    • https://cdn.sqhk.co/ruwiketi/ijLjazp/sites_to_free_ebooks_quora.pdf
    • https://cdn-cms.f-static.net/uploads/4455403/normal_606ac93d65dd9.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://vegubom.atwebpages.com/stepper_motor_notes.pdf
    • https://uploads.strikinglycdn.com/files/93a638f8-9d04-46d7-8be6-40bac344767e/concept_of_metrical_romance.pdf
    • https://uploads.strikinglycdn.com/files/8f45ab43-8000-453f-bf34-fa5b785cd68d/82558825621.pdf
    • https://uploads.strikinglycdn.com/files/a1059cf6-b2e7-44f4-a2f5-940dc1442917/vermont_service_center_address.pdf
    • http://widepidaba.atwebpages.com/potoloxumotamamatoxikugu.pdf
    • https://uploads.strikinglycdn.com/files/9fead68d-bf88-4ad6-84be-090aab1ac9c4/c_access_environment_variables.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d626.bin
ec7f4b58c26a18d215da9dcb6f0d84fb5296519fa1194edc8bd47273abae37d1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD626 5248 bytes
font_01_sfnt_off0000e812.bin
70eb4742c1eafbdf01ce187bf691f3d60bb2b1bc14683f89fd0f6981b13f41cf
pdf-font-stream PDF embedded font (sfnt) at offset 0xE812 12692 bytes