Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a1fbe7c2704ef6b…

MALICIOUS

PDF

78.4 KB Created: 2021-03-30 09:17:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: aedd51c69456ac679561a115cb039927 SHA-1: 352877c7795f02da7952a082fc5f5d2b4670a125 SHA-256: 3a1fbe7c2704ef6b0b7cb0dd09cd258f924fc02360fb4fcd871ca81f277655b9
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

This PDF sample exhibits malicious characteristics, including malformed streams and links to known malicious redirectors. The presence of a critical heuristic firing for a malicious redirector at 'https://yafferge.ru/strik?utm_term=introduction+to+business+law+pdf+download' strongly suggests a phishing or malware distribution attempt. The ML classifier also flagged this PDF with high confidence, further supporting its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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.
  • 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://yafferge.ru/strik?utm_term=introduction+to+business+law+pdf+download In PDF document text
    • https://cdn.sqhk.co/kidurukazag/axP1q0u/sniper_assassin_zombie_survival_mission_3d_download.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4410443/normal_6018686dc9a6d.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4503874/normal_5ff2c55798bac.pdfIn PDF document text
    • https://cdn.sqhk.co/gitaligido/m8TmIrt/28994251108.pdfIn PDF document text
    • https://rixemovupel.weebly.com/uploads/1/3/1/6/131606965/82651fd37.pdfIn PDF document text
    • http://bibopasaxuvibu.mypressonline.com/82242082361.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4403406/normal_5ffb407da827c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4487381/normal_603e686935084.pdfIn PDF document text
    • http://xuzerujagojagip.scienceontheweb.net/31076856600.pdfIn PDF document text
    • http://koxivesuvif.mypressonline.com/video_games_to_play_while_high.pdfIn PDF document text
    • http://wuramegojuluz.mywebcommunity.org/construction_safety_manager_salary_california.pdfIn PDF document text
    • http://rodisawikikofu.medianewsonline.com/medical_internet_of_things_and_big_data_in_healthcare.pdfIn PDF document text
    • http://kepuxom.mypressonline.com/flight_of_the_bumblebee_violin_piano.pdfIn PDF document text
    • http://riwuvodobopexu.mywebcommunity.org/balarama_digest.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4386591/normal_5fe3842d29472.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4482638/normal_6056d4c86237b.pdfIn PDF document text
    • https://cdn.sqhk.co/rogevuzazi/e1ijijo/40554292154.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486351/normal_5fe76cd78dbea.pdfIn PDF document text
    • https://cdn.sqhk.co/giboxikewev/tjebNhb/final_fantasy_vii_remake_soundtrack_plus.pdfIn PDF document text
    • https://famonusowofem.weebly.com/uploads/1/3/4/3/134349488/pafajufakalavipa.pdfIn PDF document text
    • https://getenulezawo.weebly.com/uploads/1/3/4/8/134897364/duwilukexilimakurodo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://xobebol.onlinewebshop.net/78280271867.pdfIn PDF document text
    • http://suxazetevuzo.onlinewebshop.net/fomogiwaga.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_off0000f321.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF321 5320 bytes
SHA-256: be0570168dc25f56289047f640cc0edb3c8f3116187eaf0ebaa590550e5e2c92
font_01_sfnt_off00010550.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10550 11484 bytes
SHA-256: 319c102d6f0055641ef1a8f076951084fd60034a0d1943d4f9cc8c93904e4ce1