Malicious PDF — malware analysis report

Static analysis result for SHA-256 57ef66c9ba94cb48…

MALICIOUS

PDF

80.1 KB Created: 2021-09-18 01:58:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 4fccce96bab68aab49dd2f304e6ddf1b SHA-1: 3ad06fccc9c08950c6f10cf74d123c71f2fa31fd SHA-256: 57ef66c9ba94cb48141e705a17e2a38b045b8aa03cfa46e69e7b78b912eaa4b3
164 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple external URLs, some of which are hosted on compromised WordPress sites. The presence of a 'download button' lure further supports a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 7

  • 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.
  • 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 https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/890146bc9e7bdbb9f2abb2e528f46308/lidom.pdf In PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141a3eeeca5c---52313829804.pdfIn PDF document text
    • https://wolfgang-photography.com/userfiles/files/62217468268.pdfIn PDF document text
    • http://5percent-design-action.com/upload/users/files/lofovidevutis.pdfIn PDF document text
    • https://anctools.com/ckfinder/userfiles/files/fufejijapiliwimiwovusiwu.pdfIn PDF document text
    • https://aymexco.eu/ckfinder/userfiles/files/movonadopufijen.pdfIn PDF document text
    • http://www.oomewatersport.nl/upload/files/jenokufexiv.pdfIn PDF document text
    • http://vako.vn/app/webroot/uploads/files/81382302892.pdfIn PDF document text
    • https://daynexweb.com/upload/ckfinder/files/nofovubabozizovixusatar.pdfIn PDF document text
    • http://alwaysshine.com/fileimage/file/sokumivibokubul.pdfIn PDF document text
    • http://www.icareonline.net.au/ckfinder/icare/files/xodakamimosivij.pdfIn PDF document text
    • https://equinox-e.com/upload/UserFiles/file/40635954809.pdfIn PDF document text
    • http://cp-tournament.org/ckfinder/userfiles/files/bopokidotazexawezamu.pdfIn PDF document text
    • http://atsolution.org/userfiles/file/20210911130259218789672.pdfIn PDF document text
    • https://ripedzn.com/app/webroot/files/fckeditor/file/10497604670.pdfIn PDF document text
    • https://loppisidjupdalen.se/images/uploaded/file/92786220618.pdfIn PDF document text
    • http://sro52.ru/uploads/files/nemoxavitesifenofadena.pdfIn PDF document text
    • https://rewaqousha.net/userfiles/files/49494669059.pdfIn PDF document text
    • http://tsnpharma.com/upload/files/7012972659.pdfIn PDF document text
    • https://luminex.pl/upload/file/93387666236.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614081454abbc---71520263096.pdfIn PDF document text
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131a6704deca---94485396937.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=crazy+stupid+love+full+movie+watch+onlinePDF 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_off0000d30f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD30F 11340 bytes
SHA-256: 0f0db397fde9601ce847f20e21e719313801aaee457983c6a18015a0df63780b
font_01_sfnt_off0000edb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDB0 17324 bytes
SHA-256: 2f10095176eccc21e78a17caff908ff86074aabbc86894244ab3e5421028535c
font_02_sfnt_off00011ab0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AB0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1