Malicious PDF — malware analysis report

Static analysis result for SHA-256 83af4bf2f51717b6…

MALICIOUS

PDF

86.2 KB Created: 2021-09-20 10:29:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d0f8802e92f5bea895160108aada8a5d SHA-1: bcaf9defefb6683ccaf322b233c1506c8703d14d SHA-256: 83af4bf2f51717b6b1e974b7ea18ce55a08875823a251596ad427d1915afbd1f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which are part of a link farm hosted on compromised or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing sites or download further malware. The embedded JavaScript is a common technique for initiating malicious actions within PDF documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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
  • 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 https://crewmak.ru/uplcv?utm_term=samsung+galaxy+s3+mini+data+recovery
    • http://jshtextile.com/UserFiles/file///46872143663.pdf
    • http://www.ramseier-appenzell.ch/elrada/js/ckfinder/userfiles/files/mawig.pdf
    • https://pchome.uzai.ca/upload/files/sidawupi.pdf
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/16132d2956def0---talobanemezatox.pdf
    • http://telegid.tv/userfiles/file/juvekonetorejexa.pdf
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146e40306f72---84620690531.pdf
    • http://crm333.com/documentos/file/18233561792.pdf
    • http://seasonmediagroup.com/pic/file/54582909099.pdf
    • http://selidbe-beograd.info/files/5671231906.pdf
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613ceef33711e---82593862554.pdf
    • https://mehreganimaging.com/images/upload/files/24543482788.pdf
    • http://chocoenglish.com/_UploadFile/Images/file/6845103995.pdf
    • http://studiocommercialedelpiano.it/userfiles/files/xukikajal.pdf
    • http://bhttourist.com/upload/fckimagesfile/potutekakesoletogu.pdf
    • https://trystsalonri.com/images/file/34127356644.pdf
    • https://hosrem.org.vn/ckfinder/userfiles/files/larefofipos.pdf
    • http://svaz-podnikani.cz/files/file/44204774079.pdf
    • http://maxidmum.com/images/upload/fck/file/nuwaveked.pdf
    • http://wenxuezj.com/images/File/pituxut.pdf
    • https://quimicasorocolor.com.ve/ckfinder/userfiles/files/1606953800.pdf
    • http://ecosdaliberdade.com/ckfinder/userfiles/files/34011639571.pdf
    • http://bold-iot.com/uploads/files/202109111045473303.pdf
    • https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/5dc1352783dff8c16bcf204c431b0a43/26888715598.pdf
    • http://www.chatanakonci.cz/userfiles/file/93410623447.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_off0000eb5d.bin
8774adeaedd578415b91f723514f3669e5fd87723bdf0c8c472e4a56d93bf256
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB5D 11340 bytes
font_01_sfnt_off000105e6.bin
22b0470c13885f68f5db5b3a8285699923d13ee10542745dcb802559c0636f31
pdf-font-stream PDF embedded font (sfnt) at offset 0x105E6 17888 bytes
font_02_sfnt_off00013493.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13493 16792 bytes