Malicious PDF — malware analysis report

Static analysis result for SHA-256 597afeb2d6ee0d65…

MALICIOUS

PDF

89.1 KB Created: 2021-09-07 18:55:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 155d7900d4f4e9b7ab74735b2ce1b3e7 SHA-1: ca0af20b988f9f8964e98d7614f275faac0ed4de SHA-256: 597afeb2d6ee0d65c68128a9d161bdeb7aa62d488bff2f7fe120fe00fd45ead2
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external URIs, many of which point to compromised WordPress sites acting as a link farm. The ML classifier strongly indicates maliciousness. The embedded JavaScript likely serves to obfuscate the true nature of the links or to perform further malicious actions, such as downloading a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb3113ad63e---jusopoxuwebenujifun.pdf
    • http://mannaz.pl/userfiles1/file/fuxuvinewuporuwesivi.pdf
    • https://comillaspostgrado.es/userfiles/file/29021499834.pdf
    • http://chapmanhighschoolclassof1968.com/clients/c/cb/cb1fed5110c07f199f416a264ee6943c/File/kinatititewup.pdf
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/348fadda19bf4878c06c51fe76bebb17/wumabibivesojeto.pdf
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1527d8d34e---zudirizemepu.pdf
    • http://leebyunghun.org/new/upload/board/files/5560362943.pdf
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16081f90832872---37986067113.pdf
    • http://xn----7sbezcba9a5aggb3j.xn--p1ai/ckfinder/userfiles/files/126763295.pdf
    • http://www.phsdcenter.com/temp/js/ckfinder/userfiles/files/58106683245.pdf
    • http://www.sandzthabapanel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606f89e64a5ad---95391401587.pdf
    • http://ks4073.com/file_media/file_image/file/48192779549.pdf
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16070ebacb8461---96139628294.pdf
    • http://harringtonandlombardi.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/38441223806.pdf
    • https://bursac.net/userfiles/file/tepefak.pdf
    • http://eastcoastbiker.de/sites/default/files/file/90522338035.pdf
    • http://plise.org/userfiles/file/jetemosavizupanomolimuz.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b764a075394---77389195736.pdf
    • https://rireenfrance.com/images/upload/files/5309044961.pdf
    • https://cicadit.ro/UserFiles/file/42014055457.pdf
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086976b3d2c6---95553594777.pdf
    • https://cmoretv.com/userfiles/57106761751.pdf
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16070d9f00ed3d---54978024009.pdf
    • http://jiendurancecoaching.com/ckfinder/userfiles/files/linekimuja.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=les+figure+de+style+exercice+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_off0000f3ce.bin
37ead189696467457b6eb676cf638f8751993f0234d54816d919bfa21aea0928
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3CE 19988 bytes
font_01_sfnt_off000125db.bin
934a42c04339c485700c39b289e0467796e03327a6a289fdb71e9dd21e72f88f
pdf-font-stream PDF embedded font (sfnt) at offset 0x125DB 10680 bytes
font_02_sfnt_off00013e56.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13E56 16792 bytes