Malicious PDF — malware analysis report

Static analysis result for SHA-256 7133cd47610ea508…

MALICIOUS

PDF

84.4 KB Created: 2021-09-19 00:37:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 66ea253a714be483407cd7153b8af520 SHA-1: f02f4acf3b7f8adb40349239ea63bdc1acc42e4a SHA-256: 7133cd47610ea508e2e0a4083af306cf7d3105a138bec3d8c12e719a830616cb
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or are part of a link farm designed to manipulate search engine results. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO spam. No scripts were extracted, and the document body was heavily obfuscated, limiting further analysis of specific payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://blesk-stroy.ru/userfiles/files/97903459326.pdf In PDF document text
    • http://jr.ac.th/ckfinder/userfiles/files/13247675407.pdfIn PDF document text
    • http://polyacer-ecp.com/userfiles/files/20210918_212135.pdfIn PDF document text
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/a6g6ukcf5td0b2qa0936ean9ni/palowuwegavuvawepotibo.pdfIn PDF document text
    • https://www.igescanada.com/ckfinder/userfiles/files/bepifavuw.pdfIn PDF document text
    • http://www.rpv-drachten.nl/files/file/gerubukejijibivadizobu.pdfIn PDF document text
    • http://playeasypiano.com/resources/fck_images/naruwapitili.pdfIn PDF document text
    • http://www.egavilanes.com/ckfinder/userfiles/files/84487984895.pdfIn PDF document text
    • http://flywings.sk/UserFiles/file/94589973482.pdfIn PDF document text
    • https://hoangvan.vn/wp-content/uploads/files/69962092030.pdfIn PDF document text
    • http://www.anjhimayath.com/upload/file/nawosenovuniwarozimufin.pdfIn PDF document text
    • http://sswjeans.com/files/purodadaren.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161361160c67bf---6658350401.pdfIn PDF document text
    • https://foodphotoshop.com/userfiles/files/44323384359.pdfIn PDF document text
    • http://mitchelllawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/57817442916.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1613536e679aea---25697821239.pdfIn PDF document text
    • https://bruceautoservice.com/files/file/jefakawuw.pdfIn PDF document text
    • http://cbgnfinance.com/userfiles/file/44547770594.pdfIn PDF document text
    • http://plkorea77.com/ckupload/files/3396145093.pdfIn PDF document text
    • http://teranor.com/ckfinder/userfiles/files/pedopim.pdfIn PDF document text
    • http://twtipa.com/upfile/files/2021/09/08/30568555848.pdfIn PDF document text
    • https://www.rapn.ru/ckfinder/userfiles/files/xumaxodexubomonolebu.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/161407a485873b---80568415607.pdfIn PDF document text
    • http://ifa-astrologie.de/userfiles/file/vopozosokebewonosusetar.pdfIn PDF document text
    • https://spheresignal.com/app/webroot/userfiles/files/vezezitisijimufewura.pdfIn PDF document text
    • http://bivalyracing.hu/files/file/90358877317.pdfIn PDF document text
    • http://lecieldesandes.fr/ckfinder/userfiles/files/kidudozolavegazaw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=how+to+get+free+likes+on+instagram+reelsPDF 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_off0000e558.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE558 17508 bytes
SHA-256: 8cacb5b83f6293858fd9b3fab2ac878506e92b93980af4c1578e7326c1aad881
font_01_sfnt_off00011264.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11264 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012a7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A7B 10724 bytes
SHA-256: 7ab9536890fcfd7ba7e6a73ad38057865ac36107b17009bd6695ad8b93e04a96