Malicious PDF — malware analysis report

Static analysis result for SHA-256 a087d9a94871461f…

MALICIOUS

PDF

89.3 KB Created: 2021-09-18 07:19:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 87d7e7329e8a3d355f24864d259bd9fb SHA-1: 1f702e3e8ea1b46f4b7f2bba6710e145a59fb64a SHA-256: a087d9a94871461f5ab8387259e8484ad09bfe41ae4b55eabb4220dda9f39004
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ClamAV and an ML classifier, with a critical heuristic firing for embedded JavaScript. This JavaScript is likely responsible for redirecting the user to external URLs, as indicated by the PDF_URI and EMBEDDED_URL heuristics. The presence of numerous unknown URLs suggests a link farm or phishing attempt, aiming to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://jordanadams.com/ckfinder/userfiles/files/vuzawaruzekuzapip.pdf In PDF document text
    • http://nfraccon.org/userfiles/file/49965564181.pdfIn PDF document text
    • http://ngocminhcnc.com/demo_thietbimay_24_7/upload/files/terobigo.pdfIn PDF document text
    • https://pianoinprimopianofestival.com/uploads/file/dovur.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-9-9/20210909065635689053.pdfIn PDF document text
    • http://ciarajewellery.com/editor_upload/file/63571688844.pdfIn PDF document text
    • https://mavachhaiphong.com/upload/files/zararowafegixaral.pdfIn PDF document text
    • http://piannocreativo.com/js/new/fckeditor/userfiles/file/24585169745.pdfIn PDF document text
    • https://gkia.org/kingkong/userfiles/files/42069806606.pdfIn PDF document text
    • http://avvocato-callegaro.it/public/file/tujotajevitopeja.pdfIn PDF document text
    • https://encoyun.com/calisma2/files/uploads/99528274938.pdfIn PDF document text
    • http://zjnep.com/ckeditor/ckfinder/userfiles/files/46478681536.pdfIn PDF document text
    • http://pokwuttibut.com/file_media/file_image/file/44278324485.pdfIn PDF document text
    • http://antwerp-reefer-tournament.be/argt/files/polukatetibunuser.pdfIn PDF document text
    • http://we2meeting.com/ckfinder/userfiles/publics/files/68882806591.pdfIn PDF document text
    • http://yongqingtech.com/d/files/xisemab.pdfIn PDF document text
    • http://simonkuehner.de/gfx/userfiles/files/porufepigolubemodaf.pdfIn PDF document text
    • http://gamecoast.by/uploads/files/jelebaxetesuvepaf.pdfIn PDF document text
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613b1d6d5bcb1---tilitinekudakufojadoj.pdfIn PDF document text
    • https://globalcircle.club/userfiles/file/woxomebenelakotisi.pdfIn PDF document text
    • http://optykglowacki.pl/obrazki/files/mojedeposokunubarerex.pdfIn PDF document text
    • http://yuemeism.com/uploadfiles/files/17350870041.pdfIn PDF document text
    • https://hopadive.cz/ckfinder/userfiles/files/91207210230.pdfIn PDF document text
    • http://topbuild.net/content/xuploadimages/file/xodagajoredelafodoluzu.pdfIn PDF document text
    • http://capital96.com/userfiles/file/76756590519.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=android+operating+system+lollipopPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f824.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF824 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011036.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11036 17884 bytes
SHA-256: 16ec38fb017bee8fc797f71056ea4c49ec06defe6da435b0d5344731cb976d7d
font_02_sfnt_off00013ee8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13EE8 10828 bytes
SHA-256: cebd3313100a5b82408f1e1ed71c43325de35f461baf687abebc586b71520ed6