Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2ef2b32d96db93a…

MALICIOUS

PDF

87.4 KB Created: 2021-07-08 04:06:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e637489c02f53fef464be0c8fc8efc38 SHA-1: a01371badf4b65f47771b86ae725ba57d9a5d3cf SHA-256: a2ef2b32d96db93a751fbff604ee16c45f9d837cb184aa7833d32c51ca7c377d
96 Risk Score

Malware Insights

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

The sample is a PDF file identified as malicious by an ML classifier. It contains a large number of embedded URLs, many of which point to compromised WordPress sites or disposable hosting domains, indicating a link farm likely used for SEO poisoning or phishing. The presence of multiple compromised CMS upload links and disposable hosting further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 5

  • 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://wastran.ru/uplcv?utm_term=post+occupancy+evaluation+meaning
    • http://ruegen-ferienhaus-schneider.de/userfiles/file/timiw.pdf
    • http://elcampoeco.org/FCKeditor/file/dologorirevifowiz.pdf
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/160d87570ae84e---modom.pdf
    • http://africansafaris-spain.com/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/pudatifefamib.pdf
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/ghsg9catejphcekhjc83qr7cmh/59465850242.pdf
    • https://washlounge.in/ckfinder/userfiles/files/5476171546.pdf
    • http://bangdientunhk.com/upload/files/2214202666.pdf
    • https://iescolumbus.org/wp-content/plugins/super-forms/uploads/php/files/4230c3d27216c17908909666e5cc9745/56033428216.pdf
    • http://kurier48.pl/files/userfiles/file/91466700761.pdf
    • http://kayamedbursa.com/userfiles/file/14050817662.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160750bc0c4e4a---gigilivodosezo.pdf
    • http://daotaoyduoc.org/wp-content/plugins/super-forms/uploads/php/files/4le4cqre2t2m04dg35kpndt5mp/70315160557.pdf
    • https://www.varishastalari.com/wp-content/plugins/formcraft/file-upload/server/content/files/160850c415fc84---zefudopenikimaxibidi.pdf
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b9b24be1c1---wifodeganitudibiravip.pdf
    • https://www.litesourcenc.com/wp-content/plugins/super-forms/uploads/php/files/bb9cd58f05eb3012d20b0a228fb07d73/bataxi.pdf
    • http://bigxra.com/uploadfile/file/2021062919173173499.pdf
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160a3fdce6a4cf---55198701091.pdf
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d6ae957dfc---30466505956.pdf
    • https://stopserv.ru/files/file/8561511380.pdf
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/4f9b7dcbb185769712bb56b0999ee201/63157179852.pdf
    • http://dwallacelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/42989519310.pdf
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/28566b283b6eeb27d97eb56e61b6ec81/folowu.pdf
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607b2a8ac22b8---morezeveturuwerum.pdf
    • 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_off0000f0c5.bin
6519de6bbebbefdf14477365503e32db152c14307f2d662b82308140082ea5b2
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0C5 17604 bytes
font_01_sfnt_off00011f28.bin
297f373a7e339e344dbcebc41110b0133cb71f4a15fd0a77f2e65e046e953cd0
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F28 10900 bytes
font_02_sfnt_off00013880.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13880 16792 bytes