Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8c9a9140a00540c…

MALICIOUS

PDF

70.2 KB Created: 2021-09-26 04:12:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: fc2a6e3e42b5fb8fed43ed3c289e2539 SHA-1: 9dfc326d0672f79600962c20d35d3443067491bd SHA-256: c8c9a9140a00540c12572c3a4a7c221a413088ebef38c24191a9c70e14d82136
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs and is identified as a link farm on disposable hosting, suggesting it's used to redirect users to potentially harmful sites. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://laborke.ru/uplcv?utm_term=igi+for+android+download PDF link annotation
    • http://aatmicscience.org/asuserfiles/file/56093430497.pdfIn PDF document text
    • http://www.medic-pneumolog.ro/fisiere/file/180144311.pdfIn PDF document text
    • http://genarchi.com/data/temp/file/nobepirowisorokogupinuru.pdfIn PDF document text
    • http://schoonhovensvrouwenkoor.nl/ckfinder/userfiles/files/zasubewibabawopinun.pdfIn PDF document text
    • https://getracemirates.com/userfiles/files/nonotuwaxikufulidirupuju.pdfIn PDF document text
    • https://martan.es/cenavarra_userfiles/files/pinopif.pdfIn PDF document text
    • http://upoart.com/ckfinder/userfiles/files/76853000575.pdfIn PDF document text
    • http://firesecurity.sk/userfiles/file/wudezikazatatupumojodap.pdfIn PDF document text
    • http://www.gdchgs.com/admin/img/files/58540249269.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614e8a9321fdd---75533030917.pdfIn PDF document text
    • https://transturist.transturist.com/ckeditor/ckfinder/files/files/82055676909.pdfIn PDF document text
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/f710cd16de52cc24fab1c3d2c09edb46/52482675367.pdfIn PDF document text
    • http://thanglong.vn-greenenergy.com/ckfinder/userfiles/files/33032808822.pdfIn PDF document text
    • http://siamsankyo.com/Uploads/file/24599745644.pdfIn PDF document text
    • http://fjzy18.com/image/uload/files/netamazudofigesuxoka.pdfIn PDF document text
    • https://fizjolech.pl/userfiles/file/2200577957.pdfIn PDF document text
    • http://geometramaurotozzi.it/userfiles/files/31012686868.pdfIn PDF document text
    • http://novichiha.ru/pic/file/35397143294.pdfIn PDF document text
    • http://dietmoiquangle.com/webroot/img/files/xogilima.pdfIn PDF document text
    • http://xn--80aagkbrca3apkgkee0a1bi.xn--p1ai/ckfinder/userfiles/files/37159722262.pdfIn PDF document text
    • http://chanhungcorp.com/images/uploads/files/48115423816.pdfIn PDF document text
    • https://socardan.com/userfiles/files/nufiwafibawalanifazaduj.pdfIn PDF document text
    • http://sake2metustin.com/uploads/files/80245426770.pdfIn PDF document text
    • https://thietkeweblongan.com/upload/files/36441933030.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_off0000b30c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB30C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB1E 16096 bytes
SHA-256: 26ecf08c967a2cb1ca312d92c6d4f5f296a3a71414310693bbdfdfbf0277dbed
font_02_sfnt_off0000f48f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF48F 10168 bytes
SHA-256: 81453f034122c4237d6ccc7c5537730347f68517745b33ce3c38fad1dd260c1f