Malicious PDF — malware analysis report

Static analysis result for SHA-256 42aea2819162c4ae…

MALICIOUS

PDF

94.3 KB Created: 2021-07-15 12:10:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1a46d6e903f4a801b82dab40c383085e SHA-1: afe038fefd3ab42f914375fa0d398aba885f276f SHA-256: 42aea2819162c4ae255bbf737e3fc1023aeafe042e783446ea4bf8d10f48d073
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as a phishing trojan and by ML classifiers as malicious. It contains numerous links pointing to compromised WordPress sites, suggesting a phishing or malware distribution attempt. The presence of external URIs and link farms on disposable hosting further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://trongtinpc.com/luutru/files/razirufutujike.pdf
    • http://ruoumoc.com/upload/files/33113628115.pdf
    • http://tnslib.net/userfiles/files/lokodegegomidex.pdf
    • http://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609077ea0f104---retozuwuka.pdf
    • https://bamor.org/userfiles/file/jelanaxenunezuzewuw.pdf
    • https://freedomhypnosisnyc.com/wp-content/plugins/super-forms/uploads/php/files/4422d7492e806959f52eb09478a661c8/xabubatojew.pdf
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/tf4n3qfkntpo2kvgn4b44csaqf/22338295459.pdf
    • https://urbanlivin.lu/userfiles/files/50915521233.pdf
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160bfa51131c10---67819004677.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ca41835841---24464304235.pdf
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ada7a9ed775---73628038702.pdf
    • http://brilsports.ro/userfiles/file///743922790.pdf
    • http://dnepropress.net/files/file/mubulutenisutano.pdf
    • https://whitesal.com/data/images/file/3555_20210525111320.pdf
    • http://bjjiffy.com/upload/kobofixojojogun.pdf
    • http://merlegdoktor.hu/tmp/45524207772.pdf
    • http://fishtech.org/uploads/userfiles/file/file/23482403326.pdf
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/54dfcf8df6871c9344b5bb032e4d8217/mujuvoniluwuzigakuze.pdf
    • http://bomtvplus.com/data/board/file/20210629212243.pdf
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/160738183e127b---74493996381.pdf
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/593db6b375c7e76212af0d24eda5ca8a/xujokoj.pdf
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608620fdb4773---bidurirurekugofasarer.pdf
    • http://diversecityuk.com/userfiles/file/8638993274.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=your+local+changes+to+the+following+files+would+be+overwritten+by+merge+git
    • 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_off0001053e.bin
ce07ef29286979cc5d1fd06eb9505f12ee031387496303d11c4f6b7359fe2495
pdf-font-stream PDF embedded font (sfnt) at offset 0x1053E 11412 bytes
font_01_sfnt_off00011fe1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11FE1 16792 bytes
font_02_sfnt_off000137f3.bin
0037ba3fb3a42a3cc4a19f316b38d5d605955214eacd6c6c8cb84ebad5edaf61
pdf-font-stream PDF embedded font (sfnt) at offset 0x137F3 18224 bytes