Malicious PDF — malware analysis report

Static analysis result for SHA-256 aef3fdbed7d6cea4…

MALICIOUS

PDF

96.3 KB Created: 2021-06-25 22:43:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b1d00988ccbb658639db37ae8f5316a6 SHA-1: 63077bb04866ca1881df15b32b5fcb4ca34dc5be SHA-256: aef3fdbed7d6cea47c5dbc04b8f7415d27c8ad96a315b59cc2978bc83966092c
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristic analysis revealed that the PDF contains a link farm pointing to compromised WordPress upload storage, suggesting it is used to redirect users to malicious sites. The presence of numerous unknown URLs further supports this, as they likely host malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

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 http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a940b8ead4b---ledokonaxalenulodolemof.pdf
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16070cddcf3250---suvevufexuposusiw.pdf
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbc36257a6---26665033928.pdf
    • https://airshow-bg.com/file/majapenafinufijezede.pdf
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160a7bdd084ab5---wogovapijitena.pdf
    • http://files.ibiza-ferien.de/file/fiwetefurisemewiz.pdf
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160960723ad027---tikawuvafiwe.pdf
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160919aa261ed7---18165172132.pdf
    • http://trendybiz.in/usersfiles/file/63666530582.pdf
    • http://solarhomepage.ch/fckeditor/editor/images/file/7283291347.pdf
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/236tj422replvv4l8jre49647d/71226846054.pdf
    • http://builderall.info/userfiles/file/nofejoxobasun.pdf
    • http://vorne-sitzen.eu/pcms/content/file/sibanelifekevojamena.pdf
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160770a5ec2b78---83745211201.pdf
    • https://vuaship.com/wp-content/plugins/super-forms/uploads/php/files/t1irnkpn0djtk5nn075ahhihl5/9233602689.pdf
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/efa28a10cbb9e7fae5ce7edc7f22d88e/41035073669.pdf
    • http://alpha-cp.com/userfiles/file/somanibugekukudovus.pdf
    • https://luminex.pl/upload/file/9687346980.pdf
    • https://edu-mate.kr/_UploadFile/Images/file/36328369043.pdf
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aeecd6c187a---80258147708.pdf
    • https://ceccarbotosani.ro/userfiles/file/kaxujinap.pdf
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/66jrte8o5vdmiu53gmsn9qes31/55103311950.pdf
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160babf052a7a2---68401703635.pdf
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160807409b927d---sijamoxamojalen.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=mx+player+android+2.3+6+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_off0001105a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1105A 16792 bytes
font_01_sfnt_off00012871.bin
66dbec407299ac732d91f2750bce87c76a300c091d30eeaac151222f69502ee0
pdf-font-stream PDF embedded font (sfnt) at offset 0x12871 10944 bytes
font_02_sfnt_off000141f8.bin
94970efa1102283f224f32798da5d79f6aa072fd880e63bf07e36456c0b58070
pdf-font-stream PDF embedded font (sfnt) at offset 0x141F8 19488 bytes