Malicious PDF — malware analysis report

Static analysis result for SHA-256 de5b39908ab38f41…

MALICIOUS

PDF

82.3 KB Created: 2021-09-09 06:21:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: bd217ba2c6a539411f1ea7e58479c834 SHA-1: 71f143e296e1a4149d10f34ac6ee868f3482928c SHA-256: de5b39908ab38f411e3479ef09aa4677bc03f04018e4229d94f8201ad24778b0
196 Risk Score

Malware Insights

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

The PDF contains numerous links to external resources, many of which point to compromised WordPress upload directories or disposable hosting. These links are designed to trick users into downloading further malicious content, as indicated by the 'ML_NYX_PDF_MALICIOUS' and 'CLAMAV_DETECTION' heuristics. The presence of multiple external URLs suggests an attempt to host and distribute a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://coretry.ru/uplcv?utm_term=botim+app+pc
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613074c0cc243---dunoratefupalaxuta.pdf
    • http://visusmarble.com/images_upload/files/nejejexinejimefenamit.pdf
    • https://eagleegg5k.com/ckfinder/triplebuserfiles/file/fikinoxivawu.pdf
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131f97f84ccb---wanoza.pdf
    • http://savitaco.com/uploads/images/files/tosijumezatopoxe.pdf
    • http://constantemail.com/userfiles/file/163045350148272822393.pdf
    • https://glbtrader.com/userfiles/file/xunowekizefose.pdf
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135dc632c8e9---gaxegogapog.pdf
    • http://playbabydoll.com/userfiles/file/84123741005.pdf
    • https://ambulatorioveterinariosismondi.eu/file/jipovuwirikurelebogod.pdf
    • https://bloomland.com/sites/bloomland.com/files/93714031456.pdf
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/161356ddb72fb0---tuvabewukiru.pdf
    • http://gddfboiler.com/uploads/files/zipimuxodovod.pdf
    • https://aymsoft.us/aym_image/files/livoz.pdf
    • http://0225674989.kad.tw/kads/ckfinder/userfiles/files/mukadibogelobajobezodinaw.pdf
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613852ad32d31---tufosofanivalodir.pdf
    • http://yarpb.ru/pic/userfile/bivom.pdf
    • https://rafautama.com/uploads/file/pepekiz.pdf
    • http://www.jobsincrete.gr/images/_user_na/file/takagof.pdf
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161329d3b6e64e---49794443671.pdf
    • http://sntaviator.ru/ckfinder/userfiles/files/22487940147.pdf
    • https://aviatroglo.fr/IMG/file/34230425489.pdf
    • http://officeharbor.com/pdtInfo/jabividutotibumaveseferuz.pdf
    • http://ketnoikienthuc.com/upload/files/35142908014.pdf
    • http://dogomanhnghia.com/uploads/files/lezomepekuwogurekub.pdf
    • http://sapientgenerator.ru/files/userfiles/files/40230107268.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_off0000e05a.bin
f0f02362e590adc578c5ef0ab9209ad72b1588ff4bee30d6204f4b30bdebbe68
pdf-font-stream PDF embedded font (sfnt) at offset 0xE05A 10040 bytes
font_01_sfnt_off0000f6b7.bin
3f159d97af895ef9e2d1b973fd98fe69469dfaeff4caab74a48495571f61bd2c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF6B7 17576 bytes
font_02_sfnt_off000123d8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x123D8 16792 bytes