Malicious PDF — malware analysis report

Static analysis result for SHA-256 f865dff6b33d453a…

MALICIOUS

PDF

77.0 KB Created: 2021-09-07 14:51:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 0cec3ae0e7c68d6ef19fd7e2a55fb623 SHA-1: 56c77ca914291170633c74cc138298dd6d0af2f0 SHA-256: f865dff6b33d453a0c0473a2b9c63d7d4f9ef5377e4d9e56f0b0d1db42ac1074
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to compromised WordPress sites or disposable hosting. These links form a link farm, suggesting the document's purpose is to redirect users to malicious content or phishing pages. The ML classifier strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • 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://infrive.ru/uplcv?utm_term=bang+%26+olufsen+beosound+9000+service+manual PDF link annotation
    • http://membranekeyboard.pl/_data/file/mapib.pdfIn PDF document text
    • http://fasson.vip/images/editor/files/vasarivapuv.pdfIn PDF document text
    • http://www.trotasierra.com/plugins/ckfinder/userfiles/files/16677162838.pdfIn PDF document text
    • http://codefon.hu/js/ckfinder/userfiles/files/9596091370.pdfIn PDF document text
    • https://pearproperties.in/userfiles/file/43557181882.pdfIn PDF document text
    • http://ig-einheitsloks.de/medien/file/18641466261.pdfIn PDF document text
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/qn36aabufaf99161cftevvrkv4/wilulisi.pdfIn PDF document text
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/1606e4a9821526---77762544328.pdfIn PDF document text
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/160868c269470e---pupidagokovusevel.pdfIn PDF document text
    • http://architects-desk.com/uploadsfile/63589652902.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dff69b42da4---19797154094.pdfIn PDF document text
    • https://namratalakhotia.com/userfiles/files/sekoxavenifikugeno.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/f92nle9if2vnevj628i1iefl4t/19274010696.pdfIn PDF document text
    • https://armagedonspedycja.pl/files/file/juvumoxava.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/pk62ib3m00gr61n8fdu2hf8oa2/69481221216.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/0298f3e36805263a1f3ed89875da9e55/zotuxajowiferuf.pdfIn PDF document text
    • http://autoscuolapezzano.it/userfiles/files/89220222046.pdfIn PDF document text
    • http://detskypohar.cz/upload/file/xabewizoluminolabalur.pdfIn PDF document text
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/12550aa96985f6c2ac4262919cb57a92/94357236321.pdfIn PDF document text
    • http://kadh.kr/bobod/upload/file/vetol.pdfIn PDF document text
    • http://englishplanet.info/ckfinder/userfiles/files/30725768320.pdfIn PDF document text
    • http://lobi.md/userfiles/file/fupujisulolavevawa.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16080fb9e02c48---9457317002.pdfIn PDF document text
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/53dd4c22a72748b62adfa892c8f9d426/kesepusikakunun.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_off0000cccd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCCD 9572 bytes
SHA-256: 66cf22c82ca66f80b319c593a06b26622c9d78b96234f1d81d60b8d179d275fa
font_01_sfnt_off0000e17e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE17E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f990.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF990 17400 bytes
SHA-256: cb5e740153c91a7b00ae896703fa2e822ddcfe5ac7c85b2cfc4958f6ada675fc