Malicious PDF — malware analysis report

Static analysis result for SHA-256 2df4a52a183f6a89…

MALICIOUS

PDF

70.9 KB Created: 2021-10-02 22:26:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 5c80ac0f48c4e166447750cdbfa082d2 SHA-1: 33a39fe9d2a8d29a472b0ea959c1793614d02ac9 SHA-256: 2df4a52a183f6a891142c74a48da2299e515e98af8be52669c7a315419291293
164 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. The sample also exhibits characteristics of a link farm, with numerous external URIs pointing to potentially compromised WordPress upload directories and disposable hosting. ClamAV detection as 'Pdf.Phishing.Trojan' further supports its malicious nature. The combination of these factors suggests the PDF is designed to lure users into clicking links that lead to further malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 7

  • 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 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 http://sweed-trans.eu/ckfinder/userfiles/files/48115642325.pdf In PDF document text
    • http://hanart21.com/files/userfiles/file/97620340522.pdfIn PDF document text
    • http://www.arborvitae.cz/ckfinder/userfiles/files/70436436768.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614745f07bff3---zodanupokewojikitatopim.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/161494d0b5601a---20767897165.pdfIn PDF document text
    • http://tksvolga.ru/userfiles/file/36021824602.pdfIn PDF document text
    • https://bloomeng.com/uploads/nidetomifukeg.pdfIn PDF document text
    • https://ccar.host168.com/data/fckeditor/files/77635786763.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/6ngrjaau5mf1q8sq4obg1oovkt/vuriwukewabelefebubumole.pdfIn PDF document text
    • https://longislandinvestmentadvisors.com/nini/userfiles/file/xokiwifikujuf.pdfIn PDF document text
    • http://e2ingenieros.com/ckfinder/userfiles/files/31985193240.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16148949f5cc79---10150647496.pdfIn PDF document text
    • http://855solution.com/htdocs/cljr/data/files/mapomizogil.pdfIn PDF document text
    • https://sunrisemotelbellevue.com/nbloom/fckuploads/file/16428924867.pdfIn PDF document text
    • http://sswjeans.com/files/zuduresobotorevoba.pdfIn PDF document text
    • http://orgue-chantepie.info/FCKeditor/upload/file/27455518376.pdfIn PDF document text
    • http://ux02.wadhost.com/js/ckfinder/userfiles/files/sigosuti.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16140c01281320---33090111844.pdfIn PDF document text
    • http://szmchem.com/userfiles/file/61184130402.pdfIn PDF document text
    • http://telegid.tv/userfiles/file/satimeguxuterapo.pdfIn PDF document text
    • https://kungfuclasshongkong.com/louis/taichi/ckfinder/userfiles/files/tukixesawik.pdfIn PDF document text
    • http://handsonmontessoripk.com/userfiles/files/ronunuwed.pdfIn PDF document text
    • http://palenice.net/obrazky_clanky/file/gabuwef.pdfIn PDF document text
    • http://pactolous.hu/upload/file/71256312359.pdfIn PDF document text
    • http://arcos-eff.it/userfiles/files/balifilowazeji.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=opposite+of+vicePDF link annotation
    • 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_off0000b376.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB376 10152 bytes
SHA-256: 929b4e93b296c9686f0b478c307b52bd846363b118f5ff9b611c3dbc92e91a99
font_01_sfnt_off0000ca5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA5C 17312 bytes
SHA-256: b64e9fd53c3384c383fa176d56e056b41d6cf88f8c360f6f8403495913188816
font_02_sfnt_off0000f65c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF65C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1