Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8b984e9ca2564fd…

MALICIOUS

PDF

73.3 KB Created: 2021-03-04 03:46:44 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 16e4582b740cf6e11f7f093b403055e0 SHA-1: d28bc4354cff4fbba042ae5d043ff6768889f6cd SHA-256: f8b984e9ca2564fda2d33c6be700807fd9bfe902b5b82c914ee953bb5251328d
164 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many of which are disguised as downloadable files, and is flagged by ML classifiers and ClamAV as malicious phishing content. The heuristic 'PDF_SEO_LINK_FARM' indicates a large number of external links, suggesting a link farm or phishing campaign. The presence of a download button lure further supports a phishing attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://gimoguvi.ru/123?utm_term=samsung+scx-3405w+software+download+mac
    • https://cdn-cms.f-static.net/uploads/4476766/normal_60329fa6b2f66.pdf
    • http://cg-designer.xyz/conservation_biogeographyqw63r.pdf
    • https://cdn.sqhk.co/kisesawaropo/i1giihZ/16353661020.pdf
    • https://vipapixamez.weebly.com/uploads/1/3/0/8/130814430/4533246.pdf
    • http://uchebnoe.website/jawosaralolafurinalkj6ul.pdf
    • http://storezone.info/jibiwinozomavitaruxenoo83xg.pdf
    • https://cdn.sqhk.co/favejofu/jfBghjb/simple_swot_analysis_examples_for_students.pdf
    • https://cdn.sqhk.co/jenireni/ehcOBhe/star_wars_squadrons_crossplay_vr.pdf
    • http://prizinsta24.space/achievement_motivationr3uep.pdf
    • https://tifixexeruwa.weebly.com/uploads/1/3/2/6/132682204/ceabeaf61.pdf
    • https://somubafe.weebly.com/uploads/1/3/4/4/134444697/kulevanodoj.pdf
    • https://cdn.sqhk.co/mezutorixo/VRudaeD/42275842049.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://sowezenuvafe.epizy.com/27886318227.pdf
    • http://rixojitudoj.rf.gd/how_to_use_anova_precision_cooker_manual.pdf
    • http://jutodit.epizy.com/best_buy._ca_unlocked_android_phones.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_off0000de30.bin
35502b137f93fa975ce51248be887e2413bd83cccc9143395ac5503d5a4574fb
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE30 6156 bytes
font_01_sfnt_off0000f330.bin
0280d9003f0ea44e64d96e12b19f0da09b299603415e68fd8211d0397a98ba85
pdf-font-stream PDF embedded font (sfnt) at offset 0xF330 10752 bytes