Malicious PDF — malware analysis report

Static analysis result for SHA-256 1bef2f0c5a5c67c4…

MALICIOUS

PDF

91.2 KB Created: 2021-08-03 21:58:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: cc2bc97c50face97caf99631fc1eb069 SHA-1: 751b3dd083418c8f2c4b3ce51ebbabf41bbc1237 SHA-256: 1bef2f0c5a5c67c4cb485a37ea56beca0b72e91be66d22553cbf2bdd8ff65c5a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The PDF contains a link farm pointing to multiple compromised WordPress sites, which in turn host other PDF files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of numerous links on disposable hosting and the use of UTM parameters suggest an attempt to manipulate search engine rankings or distribute content widely.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/e6195886580312d4ee375be596768bc4/kegupifur.pdf In PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/160da60e0478de---82192224116.pdfIn PDF document text
    • http://matrixuniverzum.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1609039e541c72---faxalifipave.pdfIn PDF document text
    • https://balajihighfields.in/userfiles/file/luzijenaturak.pdfIn PDF document text
    • https://www.paseppe.gr/ckfinder/userfiles/files/2702241736.pdfIn PDF document text
    • http://bizbecho.com/pa/trainstation/uploads/image/file/58018590609.pdfIn PDF document text
    • http://xinyuemu.net/assets/202106/files/20210619160138680801.pdfIn PDF document text
    • http://africa-emergence2019.com/userfiles/file/norurelerodirewawe.pdfIn PDF document text
    • https://tramhuonghanoi.vn/upload/files/rokoxakomupef.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/5798ad1b3392003e801ac3ff897155d9/fiviwa.pdfIn PDF document text
    • https://webshopplus.nl/app/webroot/files/userfiles/files/jipupuzukisamediraki.pdfIn PDF document text
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1608d2cf1b3135---xomefiduzel.pdfIn PDF document text
    • http://huucodatlanh.com/userfiles/file/lewuwonaxotawebev.pdfIn PDF document text
    • http://womenscouncildallasarboretum.org/clients/85748/File/23677154842.pdfIn PDF document text
    • http://npxbyy.com/wang3_3_10_27/Upload/Upload/file/202172480388986.pdfIn PDF document text
    • https://www.beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/8204fb2082ef729c2a3e3a161360d7ad/mebesijipekuje.pdfIn PDF document text
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/3ea29d089ff915e6143cbd912c1bad59/58908097996.pdfIn PDF document text
    • http://www.teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/51283546792.pdfIn PDF document text
    • http://brenna-ski.pl/userfiles/file/zefumukejaropeduvi.pdfIn PDF document text
    • https://wickedcheesy.com/images/file/nubig.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/95720397143.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bef66344ca1---rejoted.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/ijdme6pkgt9blacfkkb5obrr32/zedixoteborivijid.pdfIn PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/hdpi2at92kbfiul6ti0f2t6dqq/42291043308.pdfIn PDF document text
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/9c7da01f27558e7bef0d4a51da135431/dobumaluzo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=frp+bypass+tool+for+pc+2019PDF 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_off0000fd44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD44 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001155b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1155B 10840 bytes
SHA-256: 63c953d46c8ec559b903cd593f162966536bd4a5f5df294cc0ce7bc232328442
font_02_sfnt_off00012e6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E6C 18180 bytes
SHA-256: f13aa6df165415ae6b8bb2b2f22f8283e0b6492c6ca7e0145f6ba18c578d1f45