Malicious PDF — malware analysis report

Static analysis result for SHA-256 62798cb78a882241…

MALICIOUS

PDF

76.2 KB Created: 2021-09-01 16:19:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 33e181053c4e05185a43cd7ddedfeed5 SHA-1: 24810bcc59650a67e779cb66b8613c95c29580c8 SHA-256: 62798cb78a882241d7947d4ffdd45047ee7c685c6b709c382876fd23efd92542
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating it likely exploits a vulnerability or contains malicious links. The heuristics reveal it functions as a link farm, with numerous URLs pointing to compromised WordPress sites and disposable hosting, suggesting an attempt to distribute further malware or engage in phishing. The presence of external URIs and compromised CMS upload links strongly supports a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://infrive.ru/uplcv?utm_term=what+did+black+people+wear+in+the+80s PDF link annotation
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607b6e5d10af1---13904879900.pdfIn PDF document text
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b64a559ad5c---25365692454.pdfIn PDF document text
    • http://secureyun.cn/uploadfile/file///2021072600263990.pdfIn PDF document text
    • http://bscsaoner.in/ckfinder/userfiles/files/dejowiwububebadikuwejonik.pdfIn PDF document text
    • http://zerosquareonline.com/file/12235596463.pdfIn PDF document text
    • http://vinczeandlaszlo.com/upload/35497200056.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160cf5e4eb20cd---xugoziwatinoxizugiladaxo.pdfIn PDF document text
    • http://fatamorgana.fr/uploads/assets/file/misotevopajumiloxinabur.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/160e0faf6a2136---sukezonemekuponuba.pdfIn PDF document text
    • http://candientushinko.com/images/file/rokol.pdfIn PDF document text
    • http://superpart.com/files/turik.pdfIn PDF document text
    • https://www.pennlighting.com/wp-content/plugins/super-forms/uploads/php/files/34fcf000cfe1a74375fa17e74c10e11e/27350666539.pdfIn PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a5cfcb30788---kafedi.pdfIn PDF document text
    • http://sintjorisparochie.nl/userfiles/file/56828601170.pdfIn PDF document text
    • http://hiniceshine.com/upload/36811130061.pdfIn PDF document text
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/59349a97a8ca7a2b00468eb41e714d66/51540205131.pdfIn PDF document text
    • http://www.misshandicap.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607e75712d4f9---19982064653.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610796dfa0686---82224765242.pdfIn PDF document text
    • http://bookblog.kr/data/file//files/tagofiruxuf.pdfIn PDF document text
    • https://www.lavishlook.se/wp-content/plugins/super-forms/uploads/php/files/7c4f1291611ec98393b39a3e56b1acd8/xatulufaburuzalulagi.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/9bc4f5e3c5ae5de0cd5fff2ec68b2f4f/fatanonodekabezonesog.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160769df3e23ca---gutulexiwoson.pdfIn PDF document text
    • https://envomask.com/wp-content/plugins/super-forms/uploads/php/files/77d24414d7a501f42eabb1d875605f39/23077538305.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160753eab43aba---nuwusunapilali.pdfIn PDF document text
    • http://newgrids.com/userfiles/file/77809035634.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_off0000c49a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC49A 11252 bytes
SHA-256: 75e2a51b73913aab6b7c6fe86b2541bd461233b22b41911ad336f94c8025251a
font_01_sfnt_off0000dec4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEC4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f6d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6D6 17040 bytes
SHA-256: 7adf954129e913ea5d20b6c6ca6b56a3c816c745945050282b6b8b57065756ff