Malicious PDF — malware analysis report

Static analysis result for SHA-256 3227c83995cbfb54…

MALICIOUS

PDF

77.8 KB Created: 2021-06-27 23:21:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 090e439d99fc547de107714fab8395a0 SHA-1: 3e40d9e842554d0e3c09fc67fa05b0887d83dcb2 SHA-256: 3227c83995cbfb546dfb1dfc3e5b24e656f82eadbee08abd13436cb3eb57529f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. It contains numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting it functions as a link farm to distribute further malicious content. Although no scripts were explicitly extracted, the PDF structure and URL patterns are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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://krisoc.ru/uplcv?utm_term=11th+english+guide+pdf+free+download+2020 PDF link annotation
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/b526cb21e8b459fbfa13d899019213f5/dokitixuweja.pdfIn PDF document text
    • http://parkhighclassof60.com/clients/871169/File/selebezowexag.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cd6dcdfefc---melave.pdfIn PDF document text
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1e7b37941---rizepegotam.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160c35e600a798---wuwebi.pdfIn PDF document text
    • http://myredm.ru/uploads/file/wunojafat.pdfIn PDF document text
    • http://spreewaldatelier.de/img/editor/file/demovixugigu.pdfIn PDF document text
    • https://www.ideaklinik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bc020dc978---nifobo.pdfIn PDF document text
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/609bee18a278629bb3f23f0061db5c82/zuwejugapibejone.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/epfip6bbcv4ihrfhocfffl5hts/midazofugolitekezevef.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/cca317g859oun4uo561fhmria1/25795270765.pdfIn PDF document text
    • https://liniagdanskzydowo.pl/files/6914377070.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/61db3f780133b4873b9f2c96a16bef9c/sobuv.pdfIn PDF document text
    • http://stressmanagement-karriere.de/userfiles/file/91167715906.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/76b391b275c2a252285f58e2ff6a5679/75899144399.pdfIn PDF document text
    • http://instandee.com/Images_upload/files/95693059756.pdfIn PDF document text
    • http://xn--80aab8aioy.xn--p1ai/userfiles/file/gitepugogonuvibifimo.pdfIn PDF document text
    • https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/a39de2d426a8139896173777421abba0/zajuz.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608eb7a4734e0---29138576504.pdfIn PDF document text
    • https://www.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/633a92a9606972e8e0876bf0caa5b683/76323903510.pdfIn PDF document text
    • https://amd-export.com/site/upload/file/mewimuvilisamifoxu.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4ec3b4055---saxug.pdfIn PDF document text
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca79eb187f---kurowe.pdfIn PDF document text
    • http://abpaluso.com/upload/file/84276247160.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/c0otee3pmv8tasj1jjnlh2fhfr/wimupejododisalupexuvit.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_off0000cb65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB65 16940 bytes
SHA-256: 40ab6ceb118510076563ff69167beb19e19f378be93194a329b2c4585a81fcbc
font_01_sfnt_off0000f7d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7D6 11160 bytes
SHA-256: db2b146e9c058f067f7224015b71f137baa4aae79a9d1fa36a40e39af794a16b
font_02_sfnt_off000111bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1