Malicious PDF — malware analysis report

Static analysis result for SHA-256 7355f64a98f372c4…

MALICIOUS

PDF

80.2 KB Created: 2021-09-04 12:01:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: bc8d389a2bc0eac37a05da9e802c6295 SHA-1: b85845a951cef54fbd1277a83b0f2c2b054afc49 SHA-256: 7355f64a98f372c41a03e93a30d9ea215e554a1029000b362e39360ca93f04eb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document functions as a link farm, directing users to multiple external websites, many of which are hosted on compromised CMS platforms or disposable domains. The embedded URLs suggest an attempt to redirect users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://hung168.tw/UserFiles/files/28011024327.pdf In PDF document text
    • http://batiment-tunisie.com/userfiles/file/runevul.pdfIn PDF document text
    • http://projectbudapest.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1608da6e3b1cde---lanow.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1607df3ea04942---tojaroriwige.pdfIn PDF document text
    • https://www.kadinlarsitesi.org/wp-content/plugins/formcraft/file-upload/server/content/files/160855a7a49da5---fitavuwu.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a78596e2009---milifotaj.pdfIn PDF document text
    • http://aqs-group.it/userfiles/files/xowunetejepav.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/qheh9h8ias94q03k2fmi8uc6uo/51197574740.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610a602885773---38887507403.pdfIn PDF document text
    • http://nhuaduongnhapkhauaz.info/upload/files/sunerenija.pdfIn PDF document text
    • http://healingtown.org/userData/board/file/kawabovojavob.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ca20d6a804---53994807698.pdfIn PDF document text
    • https://allmassage.net/upload/file/20210514083411.pdfIn PDF document text
    • http://bwc.lt/i/92892473604.pdfIn PDF document text
    • http://duszek-lasu.pl/userfiles/file/23507718281.pdfIn PDF document text
    • https://baoyi-chuck.com/ckfinder/userfiles/files/71673611923.pdfIn PDF document text
    • http://www.apsetedavisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e6bdcbbbc7---62175472210.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/shngv0ookqruvipl6hquh4ie3l/70684493047.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608371528efe0---35400257791.pdfIn PDF document text
    • http://linuxnewyork.com/draft/media/16244378895.pdfIn PDF document text
    • http://innotack.com/userfiles/files/kakip.pdfIn PDF document text
    • https://radio-aurea.eu/files/file/pefebemo.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1607ec4c6059c3---2993976361.pdfIn PDF document text
    • http://blpest.com/UserFiles/file/80905601857.pdfIn PDF document text
    • http://studioarchterreni.it/userfiles/files/73373340575.pdfIn PDF document text
    • https://socialchangefactory.org/wp-content/plugins/super-forms/uploads/php/files/72e9852ab4afcf2d7fc61a20aaa593e3/fisimigakekabajov.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=rtf+to+pdf+c%23PDF link annotation
    • 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_off0000cbca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBCA 22664 bytes
SHA-256: 71fbb1019a582ee173f03709345dd1edde2855f0b9e7701a5ff1a28b1f0d39a0
font_01_sfnt_off00010670.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10670 9852 bytes
SHA-256: 374b5aa588cac68c3937a8ccfcd87398b3d643b9b716a4392e3838510355b7bb
font_02_sfnt_off00011c36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C36 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1