Malicious PDF — malware analysis report

Static analysis result for SHA-256 985b828847975570…

MALICIOUS

PDF

82.7 KB Created: 2021-09-22 11:35:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d8d30bb19acd465b5d4d6cf55cd7dd6a SHA-1: 3a9f3bbbd45db8eccb488a80c8ae35664f2210a1 SHA-256: 985b82884797557010cf3cbaa30cacd287dc5f4343a9ce99b871824a8dd14031
172 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and multiple external URIs, many of which point to compromised WordPress upload directories or disposable hosting, indicating a link farm designed to distribute malware. The ClamAV detection and ML classifier strongly suggest malicious intent, likely to trick users into downloading a secondary payload via the presented links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 8

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://crosswaysrecruitment.com/userfiles/file/34415886200.pdf
    • https://tramhuonghanoi.vn/upload/files/1095797586.pdf
    • https://vnycc.com/userfiles/file/sujiwixapiwutejakakepu.pdf
    • http://hasicimosnov.cz/foto/Image/file/kiselotinu.pdf
    • http://gustosandvic.com/ckfinder/userfiles/files/lojutitusi.pdf
    • https://www.lavishlook.se/wp-content/plugins/super-forms/uploads/php/files/b130c6253f784ec679a5e1b6e6eeb682/75200274939.pdf
    • http://abpjseah.news-read.com/upload/files/45784904320.pdf
    • http://farashimirooz.com/files/nirepagumonamipopizeje.pdf
    • http://tischlerei-schlusche.de/sites/default/files/file/dagitonawazimumuvoxesot.pdf
    • https://anmoul.com/userfiles/file/lelajedopenumozalolu.pdf
    • http://justsayhi365.com/uploads/file/1747447674.pdf
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/161324a6ade37a---sixopizevulowut.pdf
    • http://studiocinti.eu/userfiles/files/35052821157.pdf
    • https://jv-cms.crazy-jessie.nl/uploads/files/beduzotegapegotufaduwuru.pdf
    • https://www.growxponential.com/wp-content/plugins/super-forms/uploads/php/files/pfco7udlc3h23ktp18ne36aol4/98249159677.pdf
    • http://pastadimatteo.com/ckfinder/userfiles/files/95691484768.pdf
    • http://filtrydokoparek.pl/img/all/vinuzevubifimipuz.pdf
    • http://krasneclanky.cz/uploads/vabivasevusek.pdf
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/161423afb36aad---48212874851.pdf
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/nfkannnj9ihl4bp6q3akiqh9i5/72906608403.pdf
    • http://www.lalorraineperdue.com/documents/9230037298.pdf
    • https://imad0c0.com/js/ckfinder/userfiles/files/89098259463.pdf
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/26bf5d044063e66f73f4991b31fceee8/94760564325.pdf
    • http://seatraveltx.com/uploads/files/wotitudemumowogetab.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=hacker+baba+virtual+space+apk
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ddae.bin
3e6e212aa0a5565bafc33e08d2bd2c36ff190cc92332a5ce1911050e20133b9a
pdf-font-stream PDF embedded font (sfnt) at offset 0xDDAE 18316 bytes
font_01_sfnt_off00010d61.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D61 16792 bytes
font_02_sfnt_off00012578.bin
af3412ed50c481ca048bbe16f5b7250dfc6365e7cc868750386018ed13ef9f77
pdf-font-stream PDF embedded font (sfnt) at offset 0x12578 10532 bytes