Malicious PDF — malware analysis report

Static analysis result for SHA-256 831ba0a62f47756f…

MALICIOUS

PDF

89.2 KB Created: 2021-10-04 14:20:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 5f00d6e70c3ca46f33a3de628656f2e0 SHA-1: 4fe3b061d1f3b7b61fa62a6bafe8cb52d6892408 SHA-256: 831ba0a62f47756f12377ca47b51748afc6c913b35b66405bd2ffd953d480b1f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and a link farm pointing to other PDF files, suggesting a phishing or SEO poisoning campaign. The presence of embedded JavaScript and ClamAV detection as 'Pdf.Phishing.Trojan' further supports a malicious intent. The document body is heavily obfuscated and unreadable, but the heuristics and URLs indicate a likely phishing or malicious redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 https://huntic.ru/uplcv?utm_term=our+lady+of+mary+mediatrix+of+all+grace PDF link annotation
    • http://lso-msm.fr/userfiles/file/texebuzazojudesuxo.pdfIn PDF document text
    • http://noahmission.org/dataroom/file/78412239163.pdfIn PDF document text
    • https://contact-house.com/fckeditor/upload/file/minututuvibosur.pdfIn PDF document text
    • http://strandedtattoo.net/file/89398719445.pdfIn PDF document text
    • http://yotlist.com/uniformkontakt/userfiles/image/files/fedigizasajowa.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/cbksccero36u0ohgu3g9l183kd/46351660612.pdfIn PDF document text
    • http://architetturaurbanistica.it/userfiles/files/kolus.pdfIn PDF document text
    • http://technoprofile.ru/userfiles/file/89472340382.pdfIn PDF document text
    • http://autostyle-japan.com/js/upload/files/39400462646.pdfIn PDF document text
    • https://primer-spb.ru/files/files/vuxekotivudupepe.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/16156df67073ae---79164092091.pdfIn PDF document text
    • http://prodottoitalia.eu/userfiles/files/33965443611.pdfIn PDF document text
    • http://homeopathyhongkong.org/files/zapezidoxokume.pdfIn PDF document text
    • http://www.dfdtrading.sk/ckfinder/userfiles/files/64745493928.pdfIn PDF document text
    • http://jr.ac.th/ckfinder/userfiles/files/supuvupejazati.pdfIn PDF document text
    • http://winso.tw/userfiles/file/rumugebonowabigerumererel.pdfIn PDF document text
    • http://angelescare.com/userfiles/file/78978749427.pdfIn PDF document text
    • http://lawyergz.net/uploadfile/files/bajuxavavozibozetur.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615a11e44dcb3---25348640541.pdfIn PDF document text
    • http://em-ail.ch/pictures/2/bitevowosofelo.pdfIn PDF document text
    • http://decorstore.eu/upload/file/venabipibefijuzisadutire.pdfIn PDF document text
    • http://zoekidsworld.com/userfiles/file/jinevexefubudol.pdfIn PDF document text
    • http://eptesteplelek.com/uploads/file/45798147037.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_off0000f3d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3D3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010be5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BE5 19236 bytes
SHA-256: 5a67146e7f9335c4185ff3669a93ca07923f763ea1c651380873155cddab7ff1
font_02_sfnt_off00013de1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DE1 10888 bytes
SHA-256: 9bdb6dc950f1c1344ca2fa96b57d368c4744e2fe9ee78761703b228e353e5793