Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b08fd718898f9d3…

MALICIOUS

PDF

78.3 KB Created: 2021-08-07 12:18:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: f4c0e48deb815600087dff52e329ea5b SHA-1: bdf55426b52ff8cda9827099996c179437fe4d9a SHA-256: 7b08fd718898f9d3dbdea3e1158bdfdefb86cc3632d31d4c10e3b2df738c6a6c
156 Risk Score

Malware Insights

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

The sample is identified as a malicious PDF by multiple heuristics and an ML classifier, with ClamAV specifically flagging it as Pdf.Phishing.Trojan. It functions as a link farm, containing numerous URLs that point to external resources, some of which are hosted on compromised CMS uploads. The document body is heavily obfuscated and unreadable, suggesting it's not intended for direct user interaction but rather to host these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://arerp.kr/data/file///62632580202.pdf In PDF document text
    • http://bijverhoeven.nl/uploads/files/wirajisedilaropasekorafa.pdfIn PDF document text
    • http://studiobaliva.eu/userfiles/files/24071954630.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160981bc4ddea3---93444026401.pdfIn PDF document text
    • http://geoplan.su/userfiles/file/wafikuzevuviwi.pdfIn PDF document text
    • http://gemculture.com/userfiles/file/79168856293.pdfIn PDF document text
    • https://stef-nancy.fr/upload/document/kopapofalobawiwexikixusid.pdfIn PDF document text
    • https://srp-galabau-rostock.de/wp-content/plugins/super-forms/uploads/php/files/dbhnfd1333l0s3jg4l0mi1vs8c/51721917793.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a4e415d1d17---rikukidesunizowezi.pdfIn PDF document text
    • https://roweryelectra.pl/app/webroot/uploads/file/16224156968096.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/160df052a261bc---50053679293.pdfIn PDF document text
    • https://netpage.info/userfiles/file/roselakeges.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dfb3be16a5---nisasa.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acd4ff73431---lixuvufilejipurelaro.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/a368ae4f52f14d81ee4d370868512d37/4210621558.pdfIn PDF document text
    • http://kururlaub-ungarn.de/bilder/files/97114933765.pdfIn PDF document text
    • http://lyzebrno.cz/userfiles/file/sijimurudeveruxov.pdfIn PDF document text
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/6c140513ccc22684bb8f7617b72f3ef7/63990227597.pdfIn PDF document text
    • https://patc.fr/imagesfile/tuboju.pdfIn PDF document text
    • https://muahohangnhat.com/app/webroot/uploads/files/55266813098.pdfIn PDF document text
    • http://beastyenergy.com/userfiles/file/tuvepupakako.pdfIn PDF document text
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/p2r9r423demk7d5usvpne9eibd/15214700052.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1b0f100774---5279553633.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e18f3e7b079---bagivuz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=kgf+chapter+2+tamil+full+moviePDF 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_off0000cbe2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBE2 17064 bytes
SHA-256: a8f4199cee364cc82371ba6dcd283cb2ecb6d50f1ae4c7ad3c4cbf548a1788fd
font_01_sfnt_off0000f823.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF823 10932 bytes
SHA-256: 005fdd88986b89346b722ee624c4ad638ee6a27d254430313e7e17fe5d79c49f
font_02_sfnt_off00011192.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11192 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1