Malicious PDF — malware analysis report

Static analysis result for SHA-256 ccb37bfb35b658ec…

MALICIOUS

PDF

79.0 KB Created: 2021-08-12 00:13:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 1523e065c433fa171648bb48930f95b5 SHA-1: 6e293795f15a10c807aedb4fcf7fc4edacf7504e SHA-256: ccb37bfb35b658ec0c5bb1d8029e525c377a75eefedf8e8235cdbf99b5d1d25c
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with numerous URLs pointing to potentially compromised or disposable hosting, suggesting a phishing or malware distribution scheme. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM firings reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://jirehenl.com/userfiles/file/130617349318.pdf In PDF document text
    • https://www.charityweiss.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607c537c2512c---63523710656.pdfIn PDF document text
    • http://www.c-l-r-p.com/admin/ckfinder/userfiles/files/23149400268.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/37576289911.pdfIn PDF document text
    • http://provia-events.de/pics/fotos/1/file/kexokajafafemadozidiliko.pdfIn PDF document text
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16075a55f57061---60316369332.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3e318bed7c---lefuf.pdfIn PDF document text
    • https://abeess.com/userfiles/file/88434477674.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ef86e25b2a---bizozukuvavivasalososibag.pdfIn PDF document text
    • https://rakowka.pl/userfiles/file/paxukesefop.pdfIn PDF document text
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/5gn267jfs8q9g5jeqqdoq06pu7/64878612067.pdfIn PDF document text
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/v4nlg9sclh42uqik6i8iju0ul4/39037625552.pdfIn PDF document text
    • http://fence-alarm.com/userfiles/files/gezibodizejanilewuwob.pdfIn PDF document text
    • https://thehamptonsbloomington.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608dc87be8d09---39947424428.pdfIn PDF document text
    • http://ck-kutnahora.cz/gais/image/file/80887074337.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087350bd82b8---67096382382.pdfIn PDF document text
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/b9c13481080a82db1cd85d11a5e6c743/8996713812.pdfIn PDF document text
    • http://symbioticlifetech.org/attfile/fckimg/file///20210622215852_250894447.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=kuch+kuch+hota+hai+full+movie+eng+sub+dailymotionPDF 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_off0000cfd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFD8 17040 bytes
SHA-256: 11486b615341657c8548866fd93ba5f65effee6a1ff2089aca2001ee2961993e
font_01_sfnt_off0000fc48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC48 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001145f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1145F 11328 bytes
SHA-256: 323cec8fe7be629b430c06d4b286b8a06bf44b4438ad8879371d96b64b511267