Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdc1d2a57207aeb7…

MALICIOUS

PDF

78.1 KB Created: 2021-09-10 14:44:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 6bd85d97e62257dfe569c1fe40d0cac4 SHA-1: 4e52e09bd864b5818a9f2baeb4d5e59b2c3c5cd4 SHA-256: cdc1d2a57207aeb77a204ff40e437b97e5611cb80d3b341298f778db6eb2035e
156 Risk Score

Malware Insights

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

The PDF contains numerous links to other PDF files hosted on various domains, many of which are identified as link farms on disposable or compromised hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded URLs and link farm structure suggest an attempt to lure users into downloading malicious content or visiting phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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
  • 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 http://happinessgown.com/upload/users/files/wivotajataf.pdf In PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613361e09a72c---34890012660.pdfIn PDF document text
    • http://ortopediaszombathely.hu/editor_up/90030922717.pdfIn PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/2160ca7d0220e0daa7483a16e073a7aa/vuvuzakikiwifosoko.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/pusuxesod.pdfIn PDF document text
    • https://shih-tzu.ro/files/file/88927688790.pdfIn PDF document text
    • http://worldsocialistpartyindia.org/ckfinder/userfiles/files/jasojob.pdfIn PDF document text
    • http://35ct1.com/images/ckImageFiles/files/99140633321.pdfIn PDF document text
    • http://sellmysayarah.com/userfiles/files/70287203205.pdfIn PDF document text
    • http://bulmarconsult.com/files/bajezaba.pdfIn PDF document text
    • http://www.goldenlantern.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161326ceb3f8c7---sufurenopepilile.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/mivovirakabipikanejekuk.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/guoms8ktbu1ludrvlu8j3su2am/winod.pdfIn PDF document text
    • http://drumlockingclamp.com/FCK_Editor_Images/files/18360880922.pdfIn PDF document text
    • http://alpha-cp.com/userfiles/file/gawelunakolofe.pdfIn PDF document text
    • https://groupburuemas2.com/contents/files/fafakanelevine.pdfIn PDF document text
    • http://www.uc-kushiro.net/images/library/File/92927522831.pdfIn PDF document text
    • http://bellina.pl/userfiles/file/9338764599.pdfIn PDF document text
    • http://vlajkylevne.cz/UserFiles/File/92266917733.pdfIn PDF document text
    • http://konberdbio.com/upload/files/kebigepapozuxowirobizugik.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16133350a55148---weposof.pdfIn PDF document text
    • https://samsungdvmklima.com/upload/ckfinder/files/zezukofoxonabekodemesosij.pdfIn PDF document text
    • http://whkmradio.com/userfiles/file/93230867443.pdfIn PDF document text
    • https://thailonghoang.vn/upload/files/48088000617.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=bloons+tower+defense+6+apk+downloadPDF 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_off0000c911.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC911 19244 bytes
SHA-256: 6e8da7c3e3876b9264094f0f19dbd7ac8812f3ed48988da6716f0611a3b3b2e8
font_01_sfnt_off0000f9db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9DB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000111f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111F2 10796 bytes
SHA-256: bf44c3c34e86996aef2d6fd7bf121e78902117dc48cf4fb7b94f521e3237529e