Malicious PDF — malware analysis report

Static analysis result for SHA-256 3519d488e31423ce…

MALICIOUS

PDF

86.7 KB Created: 2021-07-04 06:27:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 37e7621684b58c2392490a04282aa5d6 SHA-1: bfbbbf516ec996d5834d799cb9a815d1fde2f2e0 SHA-256: 3519d488e31423ce1549ffead6157f4145aecee7d3d79bb49b3a6e19a329c779
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links pointing to compromised CMS upload directories, suggesting a link farm designed to redirect users to malicious sites. While no scripts were directly extracted, the presence of embedded URLs and the nature of the heuristics indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.sehersirin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fa34c88d06---gubiraw.pdf In PDF document text
    • http://mobilesamara.com/img/files/file/26374139764.pdfIn PDF document text
    • http://diamantina-joaillerie.com/ckfinder/userfiles/files/sejapa.pdfIn PDF document text
    • http://palyavalaszto.hu/teszt/upload/file/lozozonurowubodakuz.pdfIn PDF document text
    • https://tripleccompanies.com/wp-content/plugins/super-forms/uploads/php/files/cddc41ce9711941307380b43a0e657f1/30280366321.pdfIn PDF document text
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/16088ad999df4a---gasaturenagivunanenutog.pdfIn PDF document text
    • http://fotossc.pl/_files/file/99550855300.pdfIn PDF document text
    • https://fa-vietnam.com/webroot/img/files/kepisojinenerugisizob.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/36lem0rsf94pjvq1s4rltrs7g0/pebipolavopifapototipo.pdfIn PDF document text
    • http://madonnina.info/userfiles/files/buzakoxufevoxo.pdfIn PDF document text
    • http://rajskiewakacje.pl/userfiles/file/34273231872.pdfIn PDF document text
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1608f4eaa042b7---59595871501.pdfIn PDF document text
    • https://ises.ca/phpsites/vertical_living/uploads/file/vakoxuza.pdfIn PDF document text
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1609841755fc92---65632613855.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/9rsuhfmfi3ova7rhqlto7kr1c8/83046590418.pdfIn PDF document text
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/ibd7qc3lor7g3363jp2vqp5q3t/besotofikedi.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16085a2262d07c---50881787190.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae5a6e6755a---bepewapokubeviba.pdfIn PDF document text
    • https://www.pal-kont.hu/wp-content/plugins/super-forms/uploads/php/files/c422f246fd3bdbc28ca9be13dbe6b86d/wuzanuxolugixomobulonum.pdfIn PDF document text
    • https://shayangroup.net/wp-content/plugins/super-forms/uploads/php/files/8e39e213bb067352c5a541cf736447a0/vejonitililut.pdfIn PDF document text
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/18a482dc28b31d3be97533efe0f52a45/22660953348.pdfIn PDF document text
    • http://sb-78.ru/files/file/kibatajigaxobofetid.pdfIn PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1992c608d---51937718516.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160927c7bb029d---1722685670.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=cornstarch+and+corn+flour+is+the+samePDF 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_off0000ef98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF98 17196 bytes
SHA-256: 5a8765fa0e18210a04cc4dd2cee188ed66cee988ba43d4859f843c980ca49084
font_01_sfnt_off00011c99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C99 10872 bytes
SHA-256: eeec3a25f22dba020a184b62fa9fc406f07ed94416de08fd12b2280f063a28eb
font_02_sfnt_off0001358a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1358A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1