Malicious PDF — malware analysis report

Static analysis result for SHA-256 41f78c44b8ac3b69…

MALICIOUS

PDF

79.7 KB Created: 2021-09-03 18:47:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 50e8bb48176ae764e496e283137f9838 SHA-1: 47143b085c505e5bfe9ac89ab99eee736f2330de SHA-256: 41f78c44b8ac3b69a861b4458051960989fc1b3025bfb26d538ce4159420111f
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to numerous external URLs, many of which are hosted on compromised or disposable domains. The presence of multiple PDF link farm heuristics suggests a deliberate attempt to obscure the true destination or to manipulate search engine results.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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 http://abpaluso.com/upload/file/35121315304.pdf In PDF document text
    • http://vitalbafitnessclub.eu/userfiles/files/roxekopuvobiwagedopigip.pdfIn PDF document text
    • https://nanyangtextile.com/userfiles/file/61663004531.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/1609668fe95a18---pofuserojuxawuwosivo.pdfIn PDF document text
    • https://weeb.nu/userfiles/file/katagato.pdfIn PDF document text
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/i4tid7nekhj27arbpthgkrstk2/45125174228.pdfIn PDF document text
    • http://ashole.hu/UserFiles/File/xoramaputuxuriwasirarojud.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c2b42767b7a---jinubuwe.pdfIn PDF document text
    • http://iccjsc.com/images/uploads/files/12276762834.pdfIn PDF document text
    • http://ccsilver.kr/files/fckeditor/file/7804150146129c5cc8efaa.pdfIn PDF document text
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/160af9ace17d09---zakobobibi.pdfIn PDF document text
    • http://esangsok.com/upfile/files/4114303245.pdfIn PDF document text
    • http://makesrealsense.com/ckfinder/userfiles/files/fesojagekepado.pdfIn PDF document text
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160751a28da26e---72213210712.pdfIn PDF document text
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/bkoup6dsdc2jd410v356nd1v96/69258238316.pdfIn PDF document text
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16081921ea7d11---61831992923.pdfIn PDF document text
    • https://harom.ro/files/file/96688901236.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609e9a9107a98---gonubikimezimeza.pdfIn PDF document text
    • http://xn--zb0by3yusal20ak5lcidnwigi.com/ckfinder/userfiles/files/1626429492.pdfIn PDF document text
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/3vl5r7k70ui57p5mc0ju958s7i/96481796498.pdfIn PDF document text
    • https://allcreaturesinc.com/files/files/zetijoketo.pdfIn PDF document text
    • https://umartravel.com/files/gevogewovujuwa.pdfIn PDF document text
    • https://mashura.co/userfiles/files/55201379716.pdfIn PDF document text
    • http://nirmalamathachurch.org/cms_uploads/image/file/76887051314.pdfIn PDF document text
    • http://abogarestudio.com/userfiles/file/94557444044.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=neet+question+paper+pdfPDF 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_off0000d54b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD54B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ed5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED5D 16800 bytes
SHA-256: e9d9925a79e8754675dcac1dbf5209618e752fe8c1ab7e1cc10038d3440bc264
font_02_sfnt_off00011911.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11911 10668 bytes
SHA-256: 7605faca1be18da4c8be4cd1a9e82b12827a13ced3175357c239a2cbcb555315