Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5767caa63e8682c…

MALICIOUS

PDF

81.6 KB Created: 2021-09-09 04:10:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 260a798dc114353fbc9eaa43fe33773f SHA-1: 753addd1ae533bcb33e54cce1cb0df2f8a178150 SHA-256: a5767caa63e8682cae2efc6dd76a07ae605d3aa7d9c0d25ea9274defd8d72180
106 Risk Score

Malware Insights

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

The PDF document exhibits characteristics of a ClickFix social engineering attack, instructing users to execute commands directly. While no scripts were extracted, the presence of numerous external URLs and the ML classifier's high confidence score suggest a malicious intent, likely to download and execute a second-stage payload. The document's structure and the embedded URLs point towards a phishing or scam attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 5

  • ClickFix social engineering attack high SE_CLICKFIX
    Document instructs the user to press Win+R or paste a command into a terminal — consistent with ClickFix attacks that bypass macro restrictions by tricking users into running malicious commands directly
  • 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=how+to+uninstall+an+apk PDF link annotation
    • https://pinyardim.com/calisma2/files/uploads/gowuvuvi.pdfIn PDF document text
    • http://uat2.hkha.com.hk/ckfinder/userfiles/files/69511624064.pdfIn PDF document text
    • http://oprandi.it/userfiles/files/waneputapenajanex.pdfIn PDF document text
    • http://safiorida.nl/operatori/userfiles/file/7739180549.pdfIn PDF document text
    • http://chongthamnguoc.vn/img/files/30770490687.pdfIn PDF document text
    • http://humanlitech.com/files/files/turis.pdfIn PDF document text
    • https://menokatea.com/ckfinder/userfiles/files/52064799452.pdfIn PDF document text
    • http://twilaw.com/files/files/mimavugojameb.pdfIn PDF document text
    • http://lepetitjaunais.com/userfiles/file/zobabupeduwivakixome.pdfIn PDF document text
    • http://kystar.net/filespath/files/20210906063403.pdfIn PDF document text
    • http://giadinhmedia.com/uploads/files/49708283673.pdfIn PDF document text
    • https://madeirashopping.com/userfiles/file/79332062332.pdfIn PDF document text
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/9ce9cf9a5be6f43fc396dfc1d0c0e390/bowurifu.pdfIn PDF document text
    • http://tvoirostov.ru/ckfinder/userfiles/files/nosibaxo.pdfIn PDF document text
    • http://www.niceresidence.net/image/upload/File/zesebegurubuzisokinax.pdfIn PDF document text
    • https://ibrahimkoc.com/images/Media/files/65524377961.pdfIn PDF document text
    • https://fajanav.com/aym_image/files/begutazuxunuputikasilux.pdfIn PDF document text
    • https://dunaweb.co/bg_image/files/jonurevez.pdfIn PDF document text
    • https://santaclara.com/wysiwygfiles/file/27944368792.pdfIn PDF document text
    • https://pinyardim.com/calisma2/files/uploads/bogoteginamojod.pdfIn PDF document text
    • http://airsoft1.ro/files/file/52883263032.pdfIn PDF document text
    • http://s2group.pl/userfiles/file/59824815136.pdfIn PDF document text
    • http://ig-einheitsloks.de/medien/file/xajuwiwafezolidux.pdfIn PDF document text
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/16135f4485cb46---64937653804.pdfIn PDF document text
    • http://chulatutoracademy.com/chulatutor/ckfinder/userfiles/files/zibetanesibagafakemev.pdfIn PDF document text
    • http://geasit.it/userfiles/files/lefogivenano.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_off0000dbee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBEE 10284 bytes
SHA-256: 2a62ce4ecdb286346829efe51226ae81fe65d1a4947e0cb960e6767fccd2fd18
font_01_sfnt_off0000f331.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF331 17436 bytes
SHA-256: 5ec73196184fd83a23d4f1ec62f58cab7670e0fb8fccaee19a95d07fb02a79d9
font_02_sfnt_off00012073.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12073 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1