Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7b8bf527cdf2aea…

MALICIOUS

PDF

83.2 KB Created: 2021-03-18 20:56:52 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: a003757462a09508f97d54f1bcac3008 SHA-1: 1263c351f90d269429201a63b3674f623f74f2fb SHA-256: a7b8bf527cdf2aeaa2b0fb28337ce5f34cb6fbb55d8681b280ba76e09ac04974
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, containing numerous external links, many pointing to disposable hosting. The primary URL, https://botokaw.ru/strik?utm_term=what+makes+your+dryer+squeak, suggests a phishing or scam lure. No scripts were extracted, but the PDF structure and link farm behavior are indicative of a phishing or SEO manipulation attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • 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://botokaw.ru/strik?utm_term=what+makes+your+dryer+squeak PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4404738/normal_6019a47e8c82d.pdfIn PDF document text
    • http://jologedeb.getenjoyment.net/tokigejovose.pdfIn PDF document text
    • https://cdn.sqhk.co/dixejetafap/dhepbKj/e_coli_in_urine_contagious.pdfIn PDF document text
    • https://cdn.sqhk.co/libuzewis/iaFbggy/final_fantasy_14_subscription_2020.pdfIn PDF document text
    • https://cdn.sqhk.co/tazifawixax/CjicXAX/23796680326.pdfIn PDF document text
    • http://boldly-grow.com/alpha_guns_london_limitedgkooc.pdfIn PDF document text
    • http://zonitupupafof.sportsontheweb.net/characteristics_of_a_good_research_topic.pdfIn PDF document text
    • https://cdn.sqhk.co/tosilura/jilibid/bunade.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446635/normal_600cc4d44ede8.pdfIn PDF document text
    • http://omoikiri.info/pixajodopozugagovibia3zm.pdfIn PDF document text
    • http://kogegoleteneka.iblogger.org/rafevujusurikavetuwir.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448339/normal_601f711b70ea7.pdfIn PDF document text
    • https://cdn.sqhk.co/zimajigon/fhgPiis/19224217328.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://44879a12-c10a-431c-a98a-7de142752d0f.filesusr.com/ugd/bb4607_fa22755f5cdb4d5eb9dfc1540f72eb70.pdf?index=trueIn PDF document text
    • http://revobisamapekuz.epizy.com/free_counter_strike_source_warzone.pdfIn PDF document text
    • https://b3a1a1c9-4f8f-4fb8-b7cc-7339030cc889.filesusr.com/ugd/162fe6_b926ef6357ff4084aa71af9e8358fc79.pdf?index=trueIn PDF document text
    • https://bb55feb6-a0c4-48ae-8f72-aea2c45912f8.filesusr.com/ugd/b9801a_5ff107acd2954947afc0e26f358ece9e.pdf?index=trueIn PDF document text
    • https://8d2868a3-57b7-484c-81f6-493c1c4f5daa.filesusr.com/ugd/a8ca0f_b8088baa5b794873a81c5face310352c.pdf?index=trueIn PDF document text
    • https://80172413-d145-4b71-b7cf-4a007d76ad29.filesusr.com/ugd/cacfd7_7da342d8293d4073aac2ff7763c59acd.pdf?index=trueIn PDF document text
    • http://nerezusilanake.atwebpages.com/47577040531.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_off00010851.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10851 5336 bytes
SHA-256: 05feec28466b9b59a962e7082c53763df30b43288f37857cf3c685044829f201
font_01_sfnt_off00011a5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A5A 10784 bytes
SHA-256: 9be7f9bbdaaac056bb93f934fa6f31f7f8bacadfd4321ed38c018260ee7e4757