Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b6ca9105bce1e21…

MALICIOUS

PDF

79.5 KB Created: 2021-09-09 20:03:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 604673b2c8c0cf9fe8721cea5a61309e SHA-1: 5fc877ea33c3b14dc223cfdb96b2ec68d14e1137 SHA-256: 6b6ca9105bce1e2154c39e471084bb89b8c825e51dc485ef76a2160f37b88f36
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. It functions as a link farm, containing numerous URLs that point to other PDF files hosted on various websites, some of which appear to be compromised. The presence of multiple external URIs and link farm heuristics indicates a strong likelihood of redirecting users to malicious content, potentially for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 6

  • 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.
  • 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://associatedreclaimed.com/userfiles/files/fedukogojokukekomabameler.pdf
    • http://jurabos.nl/include/editor/file/66753437652.pdf
    • http://gayaarchi.com/userfiles/file/20210906140235.pdf
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/7frtqhp4c4scbu4tohfl1ea7ng/xedarexojadiwetiva.pdf
    • http://www.florentmaussion.net/userfiles/File/70335057198.pdf
    • http://espaciocultivarte.com/ckfinder/userfiles/files/53449755615.pdf
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135a011c9df4---90703164856.pdf
    • http://myshopgroup.com/userfiles/files/neremozofokikadozotagurel.pdf
    • https://at-studio.tw/app/webroot/userfiles/files/20210906_161600.pdf
    • http://qunjl.com/userfiles/files/91240845062.pdf
    • http://dulichtantai.com/files/uploaded/files/susugulobolezufun.pdf
    • https://nffcd.org/userfiles/files/43504090196.pdf
    • http://senseoftourism.dk/userfiles/file/pinekudajotabusinavuzak.pdf
    • http://vagtteam.com/userfiles/Files/39920762644.pdf
    • http://dkmmotor.com/files/userfiles/file/44764002377.pdf
    • http://openendrep.com/userfiles/files/14475946448.pdf
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/b557cd6d35276646fef5964545330ae7/jelazu.pdf
    • https://crc.creativechange.net/ckfinder/userfiles/files/rumixememulavipasuvutage.pdf
    • http://synphabase.ch/upload/file/pijasijumofaxuj.pdf
    • http://canxetaidientu.com/images/file/23939239497.pdf
    • http://reckdance.pl/userfiles/file/27102738865.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=trap+adventure+2+for+android
    • 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_off0000cd91.bin
64315abd566b32794b65bcc335a2a40bd67f37eb56902b965de93f665197d95c
pdf-font-stream PDF embedded font (sfnt) at offset 0xCD91 19452 bytes
font_01_sfnt_off00010044.bin
d8ae84a61e2150eea48bc9f66222e06888c0a912bd958779d59b763c53fcaeb2
pdf-font-stream PDF embedded font (sfnt) at offset 0x10044 10528 bytes
font_02_sfnt_off00011868.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11868 16792 bytes