Malicious PDF — malware analysis report

Static analysis result for SHA-256 644dbff78865e1e2…

MALICIOUS

PDF

88.3 KB Created: 2021-07-03 01:01:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9e7bf2e73087e9d2e715bacdb71aac99 SHA-1: c6676ae7244cefd654ccc1a8eb82e9e54e12b7cb SHA-256: 644dbff78865e1e200497a2b7d2220f9141d7082e0866b18ee254053d1578ee8
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous other PDF files hosted on compromised WordPress sites. This suggests a tactic to distribute malicious content or manipulate search engine results. The ML classifier strongly indicated maliciousness, and the presence of multiple external URIs on potentially compromised infrastructure supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://tuabogadoangel.com/wp-content/plugins/super-forms/uploads/php/files/db051426a437c31920f54cc37c483582/lenidugiwipedija.pdf
    • https://porterbrothersltd.com/app/webroot/uploads/dadaparutamuzop.pdf
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/pc58jfbsqao4n0om14mgndkhdj/40700134340.pdf
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/um7p52nj3at5nnn5qvh1b0ois6/81617705347.pdf
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/e1f5457570a50d664c8cd0f6078c5ca3/90971937170.pdf
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/160cd6c44ab460---fofomulusatamuli.pdf
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6a43a574c1---22736720278.pdf
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ace782edea7---jugokotizivo.pdf
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/ppq8f0u3a6pogqkjcsl1v5m1ha/jegamaj.pdf
    • https://www.expoagrogto.com/wp-content/plugins/super-forms/uploads/php/files/487a5c6b4b72q7ocbe1ehj0971/panobexemosakamaxabu.pdf
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c26881439d4---79738380336.pdf
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608d236aee95a---wenerarelube.pdf
    • https://universal4shipping.net/userfiles/file/76241470357.pdf
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/16092705e89ded---poweropokesok.pdf
    • https://fcksa.com/ckfinder/userfiles/files/28857597088.pdf
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608aa5c7e9aa3---tefotogavutebesagenatimex.pdf
    • https://chpcentre.com/files/file/5260072089.pdf
    • https://dagvandearchitectuur.be/_files/file/zizobejikogolebu.pdf
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/d2683a540f89e0b3af0924259d375495/73020624392.pdf
    • http://cjandjunemillerfarm.com/clients/75830/File/lizofiliwutuwuz.pdf
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/dc7d424336126983f56cb6ff25ee2e84/gijekulav.pdf
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/1608f4d2ea7b28---raxasimile.pdf
    • https://bohemiamaestro.com/webpagebuilder/ckfinder/userfiles/files/jexutulibifuwanope.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=city+of+worcester+tax+assessor
    • 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_off0000f470.bin
cfd3e70f0eb472932948d59f0f351e829dd3f1fa818ce24d13c32c9e9ab69b5f
pdf-font-stream PDF embedded font (sfnt) at offset 0xF470 10512 bytes
font_01_sfnt_off00010cad.bin
be96c170f46f0809068e1e1311a3aa5af0627d7b886cfb8d52cce4eaeb958e36
pdf-font-stream PDF embedded font (sfnt) at offset 0x10CAD 18020 bytes
font_02_sfnt_off00013c0c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13C0C 16792 bytes