Malicious PDF — malware analysis report

Static analysis result for SHA-256 4833b910b351de62…

MALICIOUS

PDF

92.3 KB Created: 2021-08-10 08:45:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: c7e922cd4848c5c5fe645ff2fbe6b437 SHA-1: 4b839482cb4b8487c04566c0d24d31e38527a3ba SHA-256: 4833b910b351de6279bdf0919f14ff06035bd1b9053dc952b1996e41717b70ad
176 Risk Score

Malware Insights

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

This PDF file is identified as malicious by ClamAV and an ML classifier, indicating it's likely a phishing or trojan delivery mechanism. The document contains numerous embedded URLs pointing to compromised websites and potentially malicious content, suggesting an attempt to redirect users to malicious sites for phishing or malware downloads. The presence of callback lure heuristics further suggests a social engineering tactic to trick users into contacting attackers.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9673

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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) or Microsoft license-boilerplate documents that carry no urgency or charge/dispute escalation.
  • 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://cructi.ru/uplcv?utm_term=one+security+antivirus+cleaner+booster+mod+apk PDF link annotation
    • http://hoondb.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607634fd9b923---lagesuku.pdfIn PDF document text
    • http://www.niziointerior.pl/upload/file/26203268229.pdfIn PDF document text
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/cf5bcb5af1df39ab501ee26914321215/gakidasesisalopojufaxulow.pdfIn PDF document text
    • http://www.peopleoftheheath.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607944039b9af---vadirupudon.pdfIn PDF document text
    • https://artenika.pl/fck/file/59079733137.pdfIn PDF document text
    • https://almuhja.ps/ckfinder/userfiles/files/linoririnujosena.pdfIn PDF document text
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/44c4bd89f047634d767caf90e76351cc/36804313817.pdfIn PDF document text
    • http://www.village-gaulois.org/gestion/ckfinder/userfiles/files/56929073829.pdfIn PDF document text
    • https://www.properties-thassos.com/wp-content/plugins/super-forms/uploads/php/files/enlj1d3067o2co3gdmjoggsmb1/34545024590.pdfIn PDF document text
    • https://airshow-bg.com/file/wokanok.pdfIn PDF document text
    • http://phillipsbricksalumni.com/clients/56168/File/26327829109.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e4882bde2d---29514824116.pdfIn PDF document text
    • http://auksozvynas.lt/userfiles/file/widamilajukefaxo.pdfIn PDF document text
    • http://csc-028.com/userfiles/file/20210708010814_kcropo.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160b075d0b4fe9---nutebesuj.pdfIn PDF document text
    • https://thietbidienmanhcuong.com/upload/files/janukilesofogerido.pdfIn PDF document text
    • https://www.mysmilestudios.com/wp-content/plugins/super-forms/uploads/php/files/02e104335a24973305efd196c1b51325/feregirane.pdfIn PDF document text
    • http://sartor.ru/upload/files/96920096728.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/fd412537477b7e9c69aae5eb02a7c48e/tefejazijiziwo.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/20db9b3e562c7e124cb9add4685c7d32/32149878885.pdfIn PDF document text
    • http://xnucleus.com/members//member_images/files/84104474626.pdfIn PDF document text
    • http://yeditepegumruk.com/userfiles/nuzonexemudopulujeruda.pdfIn PDF document text
    • https://chulintemple.org/CKEdit/upload/files/wifekegatezav.pdfIn PDF document text
    • http://lagunaapartman.hu/images/user/file/zabavafilugajorejilo.pdfIn PDF document text
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/d23c65ec1f8968b21c31c14edaf6e120/48255337740.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/tp3818f23hn527e5d53unsm28s/18820121154.pdfIn PDF document text
    • http://forglass.sk/userfiles/file/xizugoverepovegak.pdfIn PDF document text
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eb02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB02 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010314.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10314 17136 bytes
SHA-256: a23b70f0d383c83537ccbd656c88d906efa47e7446ae6acd3704bedf99b90907
font_02_sfnt_off00012fde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FDE 16144 bytes
SHA-256: fcca37035df06e555c2991ff65faa0e8497ca6423bee408ebc46b3aef925b516
font_03_sfnt_off0001455e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1455E 11212 bytes
SHA-256: 5dbdd674d76621de6fc9b309e9c09c8bde02d5a00b0f01b2e95fe101903f4db5