Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c875d2b2d489482…

MALICIOUS

PDF

94.5 KB Created: 2021-09-09 02:30:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 461b8e88f2a46b3e2ae89a53860c27da SHA-1: 8726b07505c263908178bf6131b3cb6dd6911996 SHA-256: 8c875d2b2d489482c85a355abc4933bf15f07b0105499fbed99413b3ef7a34de
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. The presence of a link farm pointing to compromised CMS uploads and disposable hosting, along with a high ML classifier score and ClamAV detection, strongly indicates malicious intent. The embedded JavaScript likely serves to download and execute a second-stage payload or redirect the user to a phishing site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 8

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://career-id.org/ckfinder/userfiles/files/kuperebawutotatul.pdf
    • http://bjaimama.com/data/upload/2021/09/file/202109021253564689.pdf
    • https://buzascsaba.hu/userFiles/file/74822563582.pdf
    • https://svenjakretschmer.com/ckfinder/userfiles/files/nawopubev.pdf
    • https://whitepalacegrill.com/userfiles/15930659589.pdf
    • https://kolegium.inaheart.org/upload/files/93843013961.pdf
    • http://maginsaatmetal.com/resimlerfiles/vokulinopenozokimidipuxal.pdf
    • https://adeptos.clevercloud.pt/images/items/files/64890141627.pdf
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/b6e87e284f13cd88bc6a1b1098e29eed/76163956059.pdf
    • https://sikanderajam.com/Robinson/ckfinder/userfiles/files/11278420461.pdf
    • http://remobudostol.pl/pliki/vogifetupebejaripapo.pdf
    • http://engineersclasses4competition.com/files/others/vakalajexid.pdf
    • http://biogenetec.tw/image/files/20210902_111824.pdf
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/a104f5805ef029b50c2ffa2574c9b787/gabovigevi.pdf
    • https://abriganature.centralcms.cloud/galeria/files/71160466257.pdf
    • http://mundori.com/js/ckfinder/userfiles/files/sizidolep.pdf
    • http://myhomeinparis.com/userfiles/files/ravuga.pdf
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134b8c1f0715---87193978167.pdf
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/02c6d9b89ea115f7eeb5747d3361918d/55786228951.pdf
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16139423b50ecb---fofokixo.pdf
    • http://jezirka-biobazeny.cz/UserFiles/File/wobavalofepobimujubuge.pdf
    • http://restauraceeverest.cz/userfiles/file/bebigexoki.pdf
    • https://xuantruongtech.com/images/ckeditor/files/nopuvivadepifev.pdf
    • https://jmtours.co/aym_image/files/85702232202.pdf
    • https://vinaarc.com/app/webroot/files/ckfinder/userfiles/files/modoluwifafo.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=after+we+collided+full+movie+free+putlocker
    • 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_off00010637.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10637 16792 bytes
font_01_sfnt_off00011e49.bin
333deea11e06e2983466771b9384a67313df9d8dba7f55a3c7f01eadd57a59c9
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E49 19536 bytes
font_02_sfnt_off000151b9.bin
fed1e642c6f114f3991f60d7c6409b6da3bc076ff5b131ea090e00c9b5e02a11
pdf-font-stream PDF embedded font (sfnt) at offset 0x151B9 10672 bytes