Malicious PDF — malware analysis report

Static analysis result for SHA-256 6839fb4769b16472…

MALICIOUS

PDF

72.8 KB Created: 2021-09-05 00:16:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 25463d5859d664b1166ca0065ca4e376 SHA-1: cc0adb02e92b98b2e387cfa783e843b126fd9ddc SHA-256: 6839fb4769b1647266cd247aaf7a261a3ccb262460b4878fd7c3b5b15b27b28b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs pointing to compromised WordPress sites, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple distinct hosts and the use of 'utm_term' parameters in some URLs suggest an effort to obscure the final destination and potentially track campaign effectiveness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://crysiq.ru/uplcv?utm_term=taxmann+gst+book+pdf+download PDF link annotation
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/160b84771e7da0---59348863434.pdfIn PDF document text
    • https://regeneracion-capilar.com/wp-content/plugins/super-forms/uploads/php/files/d372a20a29e9fe20c716bfd3acb2196d/jomizo.pdfIn PDF document text
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/aem4dlpht0rq86bsh1ooovt16a/56703816087.pdfIn PDF document text
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b352e07005f---48171739271.pdfIn PDF document text
    • https://elearning-chemistry.ro/userfiles/file/kovafi.pdfIn PDF document text
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/d5a8446b8946ec2fc116dc0faffac090/kasawasat.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608da63da20b6---tijuwa.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607ad002def20---80313767734.pdfIn PDF document text
    • http://sochisushi.nl/survey/userfiles/files/fazegifozagizuwigajofamu.pdfIn PDF document text
    • http://zl369.net/userfiles/file/bivatizat.pdfIn PDF document text
    • http://ketoanaca.com/uploads/image/files/febasobedasadubo.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/ae153d53b99dd675cb7622137ee4027e/xuzupelukowusafafow.pdfIn PDF document text
    • http://www.dawnrotaryclub.tw/UserFiles/files/sadepizifozizug.pdfIn PDF document text
    • http://doorsatyrau.com/ckfinder/userfiles/files/97191082737.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a1382e6d67---garotufonulofasop.pdfIn PDF document text
    • http://getem.pl/files/file/tabifoguliwapamipovewole.pdfIn PDF document text
    • http://nofatrans-int.com/userfiles/file/vadawomoteranikusatoz.pdfIn PDF document text
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/ngk074v5lcl1cjbavjcga94dl5/43987630031.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/9a3b55bacc2462d0b3e8fff42b3fdf2d/nabetajudutipudujapur.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b99368099f9---vibekirosokivujifuzezop.pdfIn PDF document text
    • https://varbackaforskola.se/ckfinder/userfiles/files/totuvanopupenilam.pdfIn PDF document text
    • http://mognational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091b3ebcc20a---37631863274.pdfIn PDF document text
    • https://wolfgang-photography.com/userfiles/files/nirojusono.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bad2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBAD2 10900 bytes
SHA-256: 1346a771b459b0cbf60744608a6d56da42de5d87f96cd8fd08bf25f6060de8b3
font_01_sfnt_off0000d3b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3B8 16212 bytes
SHA-256: 85c0620ccae26cf5fcb9fd8ab4d2f6756a34056d27389aead82b62740e117a54
font_02_sfnt_off0000fda8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDA8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1