Malicious PDF — malware analysis report

Static analysis result for SHA-256 8aef1b834d77639c…

MALICIOUS

PDF

71.9 KB Created: 2021-09-26 12:21:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 5b658d501ca78cf91f36c9b3723f0732 SHA-1: d7d6df6b880a8fa5b0bc7477b205242b5b878a33 SHA-256: 8aef1b834d77639c11dcbc21bc119bbf709f766761b7e3ad7caa9e6cfb5ddab5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which are part of a link farm hosted on disposable domains, indicating a strong intent to redirect users to potentially harmful sites. The presence of 'utm_term=meterpreter+commands+for+android' in one URL suggests a possible focus on mobile exploitation or information gathering.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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
  • 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.
  • 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://krisoc.ru/uplcv?utm_term=meterpreter+commands+for+android PDF link annotation
    • http://szao-spb.ru/images/news/file/36071781536.pdfIn PDF document text
    • http://benthanhsgfarm.com/images/uploads/files/63682652877.pdfIn PDF document text
    • http://assisdrive.pt/userfiles/file/dejiriromigutadawakup.pdfIn PDF document text
    • http://leadershipcareer.kr/fckeditor/_upload/file/lukeranexaxibuxoketigige.pdfIn PDF document text
    • http://studioagronomoserragiotto.eu/userfiles/files/33178541441.pdfIn PDF document text
    • http://thepducphat.com/upload/files/lezotofuletotinuresutoz.pdfIn PDF document text
    • https://eniedu.com/data/file/20210905041308.pdfIn PDF document text
    • http://specialcats.nl/media/files/lutuwuwuxovaduwij.pdfIn PDF document text
    • http://a-mega.ua/images/uploads/file/fejumotasupekevisipos.pdfIn PDF document text
    • http://capthepcongtrinh.com/uploads/news/files/55489117507.pdfIn PDF document text
    • http://joelcsimonesq.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xotigulelupod.pdfIn PDF document text
    • http://lrm.mcdonalds.ua/ckfinder/userfiles/files/84587310124.pdfIn PDF document text
    • http://architettotamborra.eu/userfiles/files/fimetun.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132be2d04ccd---23677916232.pdfIn PDF document text
    • http://brmhn.com/userfiles/file/20210913064347_0gnyoj.pdfIn PDF document text
    • https://atlaskvartir.ua/data/uploads/files/76850587494.pdfIn PDF document text
    • https://posetili.ru/userfiles/file/fulom.pdfIn PDF document text
    • https://pinyardim.com/calisma2/files/uploads/pebujemukuvatejotikiram.pdfIn PDF document text
    • http://t-eamplus.de/web/editor/files/dakedabomimadezapejoduso.pdfIn PDF document text
    • http://icaalliance.org/filespath/files/20210907165851.pdfIn PDF document text
    • http://ichieh.tw/uploads/files/202109210121335794.pdfIn PDF document text
    • https://gazeta-msp.pl/user_files/File/kopulilep.pdfIn PDF document text
    • http://fruitvita.com/files/files/rijofoxenivokedusamafito.pdfIn PDF document text
    • https://xn--80aaa1arbfjoe3bzh.xn--p1ai/data/files/kuxefudogote.pdfIn PDF document text
    • http://silver.jo/ckfinder/blanc/files/86509469842.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://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_off0000b20b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB20B 18096 bytes
SHA-256: b6e740510a507e4983f4bc286adb377ecf948f6053e3e1d27989740dd0e7809b
font_01_sfnt_off0000e136.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE136 10728 bytes
SHA-256: ffb3131cb48a1c10fd9bc76b2d5470f7cdd45ab8ff347cb8bbe41d82dd77e3e5
font_02_sfnt_off0000f9db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9DB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1