Malicious PDF — malware analysis report

Static analysis result for SHA-256 3da8d90d348553f0…

MALICIOUS

PDF

93.5 KB Created: 2021-03-23 09:04:43 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 1625cfe605bae7a1ec40028cf58421f0 SHA-1: a5dcbbbae0e6e28cea8ed88f5a160c191993e4a7 SHA-256: 3da8d90d348553f0281bbc7691c660def530c76b75ab87a806275cd79e8eb47c
184 Risk Score

Malware Insights

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

The PDF contains multiple embedded URLs, with at least one identified as a malicious redirector. The heuristic 'PDF_MALICIOUS_REDIRECTOR_LINK' and 'ML_NYX_PDF_MALICIOUS' strongly indicate malicious intent. The document body, though heavily obfuscated, suggests a lure related to writing a novel, which is likely a pretext to drive users to malicious sites for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 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://yafferge.ru/strik?utm_term=how+to+write+a+novel+step+by+step In PDF document text
    • http://copyrighthelp.info/alto_s_adventure_piano_sheet_musicgjxlw.pdfIn PDF document text
    • http://vazitafolozif.22web.org/45993798638.pdfIn PDF document text
    • https://sasofisapen.weebly.com/uploads/1/3/4/5/134590640/537b76cb7dc98d1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375908/normal_602a01c939fe9.pdfIn PDF document text
    • http://xanusojuruxu.sportsontheweb.net/figure_drawing_book.pdfIn PDF document text
    • http://zegererevez.medianewsonline.com/dungeons_and_dragons_dice_mould.pdfIn PDF document text
    • https://fajesafopumusid.weebly.com/uploads/1/3/1/8/131871419/xanuv.pdfIn PDF document text
    • https://nidiladidubupa.weebly.com/uploads/1/3/4/7/134753920/9117703.pdfIn PDF document text
    • http://notdull-eng.online/pawedarewutajcgy2g.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4443595/normal_5ffb147d431a9.pdfIn PDF document text
    • http://doucheop.xyz/down_the_rabbit_hole_walkthrough_castlebq2v3.pdfIn PDF document text
    • http://umkatrade.ru/56030540463zuln8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421036/normal_602e3d6591087.pdfIn PDF document text
    • https://wazaxilam.weebly.com/uploads/1/3/4/7/134726650/kutegabazib.pdfIn PDF document text
    • http://bodaweziwov.mypressonline.com/85953282343.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4457005/normal_5fcbbb4df3cf4.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/e37398c0-46f2-4367-a587-4fe5a2f6ca97/gixenewibupuximod.pdfIn PDF document text
    • http://xeziredo.epizy.com/leica_geo_office_user_guide.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5ba54dd8-450a-425e-a5d6-617aaaa7645c/tuninutedawalosugin.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9c3fd79c-b34d-4c61-8157-bd10f0180e63/better_than_before_books_quotes.pdfIn PDF document text
    • http://bapibalapu.rf.gd/alter_ego_5_french.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001121b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1121B 5168 bytes
SHA-256: 63e217f010dbf5e397ff16f6f73aaf22dac5bb7d9b1d8c75967065230ef0a080
font_01_sfnt_off000123ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123CA 1800 bytes
SHA-256: 8347046c4e129bc95bc0810e750dbeeef13dfe3e5f1a3553373f678b31a05277
font_02_sfnt_off00012cab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CAB 11364 bytes
SHA-256: eaa68f22c48685a338ec5ebd093f1093651b1f905586e16ce192d95dee32a2a8
font_03_sfnt_off0001537c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1537C 16036 bytes
SHA-256: 354dce64f07f3d7acdf6a04edf763950ffbfec4edcbb4bfe17b65a83544077bb