Malicious PDF — malware analysis report

Static analysis result for SHA-256 db5c28afc9d9ee5a…

MALICIOUS

PDF

156.4 KB Created: 2021-07-06 09:44:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: eb33d56d1ade16f94b00b17a3348ebb0 SHA-1: 009b329712ad5670420845821e7fe78f567622ad SHA-256: db5c28afc9d9ee5ae62d03f676d8c83e1fb9f3cef709bf482fef3855b18658b6
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm or SEO manipulation attempt. The ML classifier also flagged this PDF as malicious. While no scripts were extracted, the presence of these links and the heuristic firings suggest an attempt to direct users to malicious or compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9845

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://webmenuplus.com/images/file/90097484736.pdf
    • http://mspchicagolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/82896638873.pdf
    • https://coonvalleycc.com/userfiles/file/fojotubusofudef.pdf
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/16087a63527e3a---kawiditediwokebiduzu.pdf
    • http://usaoxin.com/userfiles/2021-6/file/1991545644.pdf
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/ubk960l866da6oltrh5l3ec3pl/botomokopabijegifo.pdf
    • http://immopolignano.lu/images/93727810801.pdf
    • https://pinotcar.com/wp-content/plugins/super-forms/uploads/php/files/72c0366e0018fb18eb6dec18e2fce2e9/zepazuwufufidebotutib.pdf
    • http://classicalgardenstatues.com/uplds/file/noburabat.pdf
    • https://tonitomov.com/picture/file/2225711168.pdf
    • http://bernardthevenet.fr/ckfinder/userfiles/files/66371721596.pdf
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/160820f0504044---kizulubajukimekobip.pdf
    • http://vincentpopetutoring.com/clients/d/dd/dd6b7bcf94cac99d3bed97cf8166637b/File/lalaminemiwavapebefaxo.pdf
    • https://people11people.com/uploads/File/8163150926.pdf
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/8ctb0hargi6abdihl9g6njq2is/73118951147.pdf
    • http://doo-san.com/userfiles/file/20210518210123.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609abc390318e---bawewegizitom.pdf
    • http://zabradli-znerezu.cz/userfiles/file/85955921864.pdf
    • http://ibiforstarlight.org/clients/3/3c/3cfcca4e360ca8807b7dd7d6e7cbeae0/File/vofugeju.pdf
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a60949410e0---38547485244.pdf
    • https://razdolle.by/wp-content/plugins/super-forms/uploads/php/files/1fgjhb7bauflg6fcn1s3uearj2/71804179829.pdf
    • http://fritz-fahrlaender.ch/download/97211389962.pdf
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c07a05de0ae---zumanagigibisu.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=discrete+mathematics+and+its+applications+7th+edition+pdf+solution+manual
    • 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001db01.bin
703724f25b6a74ab05caf06b3062c9a587ee53cf61369e459f88541cf89c8cee
pdf-font-stream PDF embedded font (sfnt) at offset 0x1DB01 16208 bytes
font_01_sfnt_off0001f0a3.bin
f8325b55c2c5bf1fa9af9561937c0c15f1c146c39975ce70fc04fbd0755f47e9
pdf-font-stream PDF embedded font (sfnt) at offset 0x1F0A3 21372 bytes
font_02_sfnt_off00022966.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x22966 16792 bytes
font_03_sfnt_off0002417d.bin
59c0195cd834c3d6fb7f63958b1fd223ca49985355297d03c0a652cc5c67888d
pdf-font-stream PDF embedded font (sfnt) at offset 0x2417D 11036 bytes
font_04_sfnt_off00025ad0.bin
77665ae1174c0f16a6bbc1a61e04cd571a6aa5b3adfcf7fff93ae8c44fd90beb
pdf-font-stream PDF embedded font (sfnt) at offset 0x25AD0 1340 bytes