Malicious PDF — malware analysis report

Static analysis result for SHA-256 65f931e124bf7dd4…

MALICIOUS

PDF

69.4 KB Created: 2020-11-29 11:28:26 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 608f7b8664e1ec2c9e1bb8f56e29ef81 SHA-1: 73b1cc100eed009826f2c57de400625303ea12ae SHA-256: 65f931e124bf7dd4692f5cc028f7676d3c572ed25078098eb864d99e2dbce535
156 Risk Score

Malware Insights

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

The PDF file, disguised as 'Sql server interview questions and answers pdf', contains numerous external links, with a critical heuristic identifying a link farm. One prominent URL, 'https://traffset.ru/123?utm_term=sql+server+interview+questions+and+answers+pdf', is likely used for phishing or to host a malicious payload. The ClamAV detection and ML classifier strongly indicate malicious intent, classifying it as a phishing trojan.

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-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://traffset.ru/123?utm_term=sql+server+interview+questions+and+answers+pdf
    • https://cdn-cms.f-static.net/uploads/4370266/normal_5fc19ed7aaf0a.pdf
    • https://cdn-cms.f-static.net/uploads/4407100/normal_5f9f3b0428758.pdf
    • https://cdn-cms.f-static.net/uploads/4370062/normal_5f8807471bac3.pdf
    • https://cdn-cms.f-static.net/uploads/4368748/normal_5f8a6a7518ace.pdf
    • https://cdn-cms.f-static.net/uploads/4371799/normal_5f97350ebda20.pdf
    • https://cdn-cms.f-static.net/uploads/4447280/normal_5fa5e4f363ddc.pdf
    • https://xenapake.weebly.com/uploads/1/3/4/3/134353424/853e4.pdf
    • https://cdn-cms.f-static.net/uploads/4447888/normal_5fb7b92f17008.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/nowonovege/mazepuvifit.pdf
    • https://uploads.strikinglycdn.com/files/62037a3e-3507-4c8b-bc23-b95cd64a1377/vuvivogawezupu.pdf
    • https://s3.amazonaws.com/sukobogixe/descargar_chiasenhac_er_apk.pdf
    • https://s3.amazonaws.com/laradusa/zudunabipev.pdf
    • https://uploads.strikinglycdn.com/files/3dacb79c-3258-4c50-91bd-8a9b11b2ecf7/topigugewi.pdf
    • https://s3.amazonaws.com/henghuili-files2/lubowijele.pdf
    • https://s3.amazonaws.com/topipovikapari/27368845995.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_off0000d0e2.bin
8554362c40252b485594a5805f8b5d6b7ae3052b21f094fd7a2f2b23f3f90b9e
pdf-font-stream PDF embedded font (sfnt) at offset 0xD0E2 5416 bytes
font_01_sfnt_off0000e370.bin
0aff2e3ac7d9d976ea5a002743b9ec61f1808e56fd89c03b5b16cd0176332a7a
pdf-font-stream PDF embedded font (sfnt) at offset 0xE370 10860 bytes