Malicious PDF — malware analysis report

Static analysis result for SHA-256 84449cfc74ad4b39…

MALICIOUS

PDF

47.5 KB Created: 2020-09-30 16:02:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: a786215abf84de5d3200b799b51a191c SHA-1: a82ea0afc5203808601c1ff67b00ce9a3e478a03 SHA-256: 84449cfc74ad4b39a1e6aae2ea3133e804d98d9bd0025cc62e146350495a0f1e
184 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs pointing to other PDF files, many hosted on disposable domains. One URL, https://cctraff.ru/strik?keyword=antithrombine+3+pdf, is identified as a malicious redirector. This suggests the document is part of a link farm or SEO poisoning campaign, designed to lure users to malicious content or potentially download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • 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.
  • 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://cctraff.ru/strik?keyword=antithrombine+3+pdf In PDF document text
    • https://site-1036811.mozfiles.com/files/1036811/lutigukiwigika.pdfIn PDF document text
    • https://site-1036951.mozfiles.com/files/1036951/35370676000.pdfIn PDF document text
    • https://site-1036920.mozfiles.com/files/1036920/54759684155.pdfIn PDF document text
    • https://site-1036722.mozfiles.com/files/1036722/90138017518.pdfIn PDF document text
    • https://site-1036852.mozfiles.com/files/1036852/73890310798.pdfIn PDF document text
    • https://site-1037029.mozfiles.com/files/1037029/25729794451.pdfIn PDF document text
    • https://site-1037266.mozfiles.com/files/1037266/munisixupojibuginedeno.pdfIn PDF document text
    • https://site-1037260.mozfiles.com/files/1037260/vomijuvenabirafumufizipev.pdfIn PDF document text
    • https://site-1036639.mozfiles.com/files/1036639/xujudazubejijuzipopupi.pdfIn PDF document text
    • https://site-1036861.mozfiles.com/files/1036861/4368329531.pdfIn PDF document text
    • http://tovuj.robertlpalmer.com/uploads/1/3/2/6/132683209/pudere.pdfIn PDF document text
    • http://kavitu.hackettville.com/uploads/1/3/1/4/131482975/d3ade.pdfIn PDF document text
    • http://revudaxev.georgeflcharlesairport.com/uploads/1/3/0/7/130775136/388e9.pdfIn PDF document text
    • http://files.matthewcoatney.com/uploads/1/3/1/4/131407284/sezarufemumomore.pdfIn PDF document text
    • http://files.batterypowered.co.uk/uploads/1/3/0/8/130874668/6631c2872f3.pdfIn PDF document text
    • http://juvotosak.restorationalleydiy.com/uploads/1/3/0/7/130740537/varin.pdfIn PDF document text
    • http://files.gypseyteague.com/uploads/1/3/0/7/130776861/denalepusokapis-pojefuv-wutijix.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005ca4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5CA4 5156 bytes
SHA-256: ee95118f4128234f21c6b12ab52906a09159777613b4a2de42e7e01a8f8ed38c
font_01_sfnt_off00006e06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6E06 15432 bytes
SHA-256: 66ca6b14f99979273cc02904e38d8d26a4550eac91a6c73b36e5ae82e99c842e
font_02_sfnt_off00009bd6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x9BD6 16204 bytes
SHA-256: e93acd332f5893643511f4cefd38969ad5c744ad1b08842a788b6be7d277dd15