Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4b63c0d00f15735…

MALICIOUS

PDF

79.2 KB Created: 2021-02-27 05:47:32 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: b6d7b577da432e807aa054ca2b743831 SHA-1: 592ac2b37d81279efbee82f3e1fd7ace35a27a28 SHA-256: d4b63c0d00f1573591ad9d85862c7f54eb960c731f42538ecb563bf4eadf5bae
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. It contains a large number of external links, many pointing to other PDF files, suggesting a link farm or redirection mechanism. The embedded URLs and the heuristic 'PDF_SEO_LINK_FARM' indicate an attempt to drive traffic to potentially malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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/123?utm_term=el+conde+de+montecristo+pelicula+1975+ver
    • http://grafoanaliz.ru/codycross_answers_group_53_puzzle_1qqzbk.pdf
    • https://cdn-cms.f-static.net/uploads/4465397/normal_6009d2d9ec95f.pdf
    • https://cdn-cms.f-static.net/uploads/4445889/normal_6023dc6d3c786.pdf
    • https://static.s123-cdn-static.com/uploads/4403688/normal_60048fdfa7ccc.pdf
    • https://static.s123-cdn-static.com/uploads/4379606/normal_5ff035fd57cfc.pdf
    • https://static.s123-cdn-static.com/uploads/4389603/normal_5ff40a4145c08.pdf
    • https://cdn-cms.f-static.net/uploads/4372072/normal_603917572ddbd.pdf
    • http://microbladingcertificationdfw.org/xejaruwijagiromurilapukomppca7.pdf
    • https://cdn-cms.f-static.net/uploads/4489028/normal_602470568101a.pdf
    • https://cdn-cms.f-static.net/uploads/4495999/normal_600fa7431e5ca.pdf
    • http://zelopaqq.xyz/74667986010fl7bh.pdf
    • https://static.s123-cdn-static.com/uploads/4469355/normal_5fee69bd1b990.pdf
    • https://mapivabivex.weebly.com/uploads/1/3/0/7/130776319/8367758.pdf
    • http://opensalle.xyz/jikapaf7vwv.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://bumunosusub.epizy.com/revugidazipefirujexutit.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_off0000f47e.bin
e3567eafeca4e63f9e5a8e663d2a76b7ddf8e1baef3fcafeefe61c202b5951bc
pdf-font-stream PDF embedded font (sfnt) at offset 0xF47E 5648 bytes
font_01_sfnt_off000107b0.bin
9ce6694cf9cd1cbc5e5fc75de01e8aa4c98fa79a291b38b56611f8d526eb9ebb
pdf-font-stream PDF embedded font (sfnt) at offset 0x107B0 12048 bytes