Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c80d285d7a486cb…

MALICIOUS

PDF

88.5 KB Created: 2021-07-02 23:14:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: b14858026450b947cc3d709f7b54f9f9 SHA-1: b3236e6c75e835b944429e49f983201105121c73 SHA-256: 8c80d285d7a486cb4c974027e9d2de5a73b1d38605c66263aa5957225947a1c1
164 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent, likely involving exploitation of PDF vulnerabilities to execute the embedded JavaScript.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://synerhu.ru/uplcv?utm_term=rational+choice+theory+criminology PDF link annotation
    • http://bmcnx.com/userfiles/file/8682524213.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/80emk6701pfbffj9u8fqe7rjd7/befevuxodewa.pdfIn PDF document text
    • https://etonbio.com/newsLetters/images/file/44271786675.pdfIn PDF document text
    • http://rayanchem.com/d/files/5698534733.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e59fac3cc8---25520045045.pdfIn PDF document text
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d9dba569ea9---16265295470.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16082b5a89dda2---raxapirujosunuduxowaginal.pdfIn PDF document text
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b24f91e1e52---bubajufolexidigimijajapow.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16090858b55525---40243461988.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606f14695fb17---zimokuxusojalekolex.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3e9e3e8ec2---wobupidobapadajitulebi.pdfIn PDF document text
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/g6jshs1e7vi4md1tk3jimjc0lp/80453134190.pdfIn PDF document text
    • https://www.proctoloji.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079feb1d1974---51412545124.pdfIn PDF document text
    • https://asthasupermarket.com/userfiles/file/50006293353.pdfIn PDF document text
    • http://salkim.com/userfiles/file/76557584204.pdfIn PDF document text
    • http://studiospazioambiente.it/userfiles/files/1242399319.pdfIn PDF document text
    • https://www.bakirkoytemsilcisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160807a2d63ce0---87507379094.pdfIn PDF document text
    • https://soyana.de/js/ckfinder/userfiles/files/19178527071.pdfIn PDF document text
    • https://cuisinescartier.ca/upload/editor/file/tewetetusoleda.pdfIn PDF document text
    • http://anipetkingdom.com/webroot/img/files/wirixavunafezi.pdfIn PDF document text
    • http://staging.impactredevelopment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607393d8ef6c9---95435849104.pdfIn PDF document text
    • https://caravanandre.it/wp-content/plugins/super-forms/uploads/php/files/cac06c5550cb84d569f8ad352556d5c8/wezibonisevi.pdfIn PDF document text
    • http://stigstudiotecnico.it/userfiles/files/lokojetesoxupusejuwegiz.pdfIn PDF document text
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077ea66d773e---venovuduvupaj.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_off0000f77b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF77B 17232 bytes
SHA-256: df873ada9696d20936041527edbe55a70f06bea72d27a8bce6b57bfc6adddeb8
font_01_sfnt_off00012448.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12448 10668 bytes
SHA-256: d4aab44ab70cb6167b5b36a9a9e9140358125e053355963687ba3e832b7f7a53
font_02_sfnt_off00013c94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C94 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1