Malicious PDF — malware analysis report

Static analysis result for SHA-256 1895b51c5f360066…

MALICIOUS

PDF

68.3 KB Created: 2021-09-13 01:37:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: ff67052deb8fad20f1678091e5f80367 SHA-1: 1b3347d8618cc37f0d39cff5cbcc9f51924d609a SHA-256: 1895b51c5f360066a34b926511af8746ccc6bcff48df98bef0dd414d65e2c75b
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it's an image-based lure designed to trick users into clicking external links. The document body is heavily obfuscated, but the presence of numerous URLs, many pointing to compromised CMS uploads and disposable hosting, strongly suggests a phishing or malware distribution scheme. No scripts were extracted, but the PDF structure itself facilitates the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9851

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://come2menorca.com/images/file/50623779159.pdf In PDF document text
    • http://klhl.com/userfiles/file/fenudujumamonogixeduvorum.pdfIn PDF document text
    • https://lerong.vn/wp-content/plugins/super-forms/uploads/php/files/e7f065bce95b85d139552cf095c18df5/kupatojovexefi.pdfIn PDF document text
    • http://sgrappresentanze.eu/userfiles/files/89822518986.pdfIn PDF document text
    • https://benqmusicworkshop.com/fupload/file/23622336197.pdfIn PDF document text
    • http://sunway.me/uploads/file/10115259349.pdfIn PDF document text
    • https://iwistw.com/upload/files/benumo.pdfIn PDF document text
    • https://whatproperty.ng/ckfinder/userfiles/files/misejejoremaxeza.pdfIn PDF document text
    • http://kxqcgs.com/filespath/files/20210913060235.pdfIn PDF document text
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613beeb192df5---51504835879.pdfIn PDF document text
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/8p17caet3554d53pd5f6duv7gd/27004467930.pdfIn PDF document text
    • https://www.wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/kiradazulan.pdfIn PDF document text
    • http://marinaxaraes.com.br/ckfinder/userfiles/files/59827994902.pdfIn PDF document text
    • http://www.hkimm.hk/_bin/ckfinder/userfiles/files/koxavokagi.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/6r4inqm4t1f90hv3vj4f44mgb4/zixonutesugoxesoxod.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16137bac74ed9b---kiwowevafebuj.pdfIn PDF document text
    • https://bahia-group.com/ckfinder/userfiles/files/53082377065.pdfIn PDF document text
    • http://omni-links-europe.com/images/blog/file/juvanumexosugozedilibiv.pdfIn PDF document text
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/sk50jphvph527jh56nf5a7sbnt/texabeku.pdfIn PDF document text
    • http://chataphan.com/file_media/file_image/file/zoler.pdfIn PDF document text
    • http://sreema.org/FCKeditor/file/91589736690.pdfIn PDF document text
    • https://tutorlookup.com/ckeditor/ckfinder/userfiles/files/78603360860.pdfIn PDF document text
    • http://fipjp.com/userfiles/file/jemovorokifuxitede.pdfIn PDF document text
    • http://websteravelandscaping.com/editorData/file/lifemuvunenepoxotunukawip.pdfIn PDF document text
    • http://robertwestlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/wozedazuwegefe.pdfIn PDF document text
    • http://conblocmanado.com/pics/file/gomikujolaxokumonuwikat.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=how+to+lock+a+album+on+androidPDF 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_off0000b170.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB170 13692 bytes
SHA-256: 3a4512f38c5cfbd0b4366014ab0f57b802c4b44e96d07f38fe48e4bd635a191d
font_01_sfnt_off0000d2f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2F7 10640 bytes
SHA-256: dd07ff2bfa0eb617cf0c5c38a5733901d3c4f713884daae9056d63c86ec25d4d
font_02_sfnt_off0000eb41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB41 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1