Malicious PDF — malware analysis report

Static analysis result for SHA-256 38210862e4e71df0…

MALICIOUS

PDF

87.4 KB Created: 2021-09-16 20:32:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c50587053d9de55977fdd588504c3138 SHA-1: ca0f3a8cdd16ee0df04969d6fbcd91680ae2be0a SHA-256: 38210862e4e71df0520d376977b32778fc5dbc871a356f6d13fc5d698212e00f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as a phishing trojan and a machine learning classifier indicated a high probability of maliciousness. It contains an embedded JavaScript stream and numerous URLs, many of which point to compromised CMS uploads or disposable hosting, forming a link farm. This suggests the document's primary purpose is to lure users to external sites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://cbafjvn.com/uploads/userfiles/file/56503309524.pdf
    • https://tvmreza.tv/ckfinder/userfiles/files/30197459505.pdf
    • http://realcomfort.ru/content/upload/file/3905532575.pdf
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1612fdd0499871---25443386991.pdf
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/6baaaa050d46357a27b207d540a204c6/ponagenid.pdf
    • http://optometrystaprzemysl.pl/userfiles/file/91502132584.pdf
    • http://boekenwinkelindex.nl/images/uploads/43227424417.pdf
    • http://rsport.eu/yonexshop/static/file/gogijonu.pdf
    • https://rent-1.es/ckfinder/userfiles/files/voduvijironede.pdf
    • https://fullmagicweekend.com/ckfinder/userfiles/files/76707057352.pdf
    • http://xn--tnqz8hz5cb8l.com/upload/files/zinofosejagisaraxof.pdf
    • http://xn--z92bzy85x.com/userData/board/file/tabazinexepisozi.pdf
    • https://kozmetikadunakeszi.hu/userfiles/file/fiwexasakikajolilapuduzeg.pdf
    • http://nassagroup.org/app/webroot/js/ckfinder/userfiles/files/zitajovanisigabebidotit.pdf
    • http://fotografoenricogiampieri.it/userfiles/files/54673679407.pdf
    • http://vaithun.net/upload/files/85129367563.pdf
    • https://bisleri.genefied.co/ckfinder/userfiles/files/7171304473.pdf
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16138abfd59ddb---58718997295.pdf
    • http://analhospital.net/file/files/pabeloropa.pdf
    • https://thehouseproduction.net/file/mojejasolemajajitobaj.pdf
    • http://savalis.ru/userfiles/file/vapajobabik.pdf
    • http://www.waetsukai.jp/system/ckfinder/userfiles/files/26494427075.pdf
    • https://bostaninsaat.com/image/files/92261780345.pdf
    • http://www.facyt.com.ar/ckfinder/userfiles/files/dezotaf.pdf
    • http://etoprosto.ru/ckfinder/userfiles/files/78323042523.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=best+war+games+android
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f33b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF33B 16792 bytes
font_01_sfnt_off00010b4d.bin
4d7d852bdf698744b549e43288a0e7b8bb436e5095033b5c6e05be2af0e8aff4
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B4D 17048 bytes
font_02_sfnt_off000137a9.bin
18c1ed0ae5d6fdcc5cea9f69ac96151613cd2e53777396c40b9a21f6bedbb9e4
pdf-font-stream PDF embedded font (sfnt) at offset 0x137A9 10684 bytes