Malicious PDF — malware analysis report

Static analysis result for SHA-256 918854a17c10bca1…

MALICIOUS

PDF

97.4 KB Created: 2021-06-27 10:11:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0443e5bf29774fd98dbe9dba3f5ef384 SHA-1: e0c9b29e86a75e897eae7c4407fc4e5f25b5e67b SHA-256: 918854a17c10bca1b08839bb01539f18499d492ad263479a3a2c567231f114ba
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 multiple compromised websites, likely for SEO poisoning or to host further malicious content. The presence of numerous links to WordPress upload directories suggests an attempt to leverage compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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://medicinasolidale.org/wp-content/plugins/super-forms/uploads/php/files/07011e4d7d48b299f1e713c5501c68c3/vowilelixefila.pdf
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/4051654c6ba5d3931dcc64ab4831683f/64471967120.pdf
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/42838c04541fd0eec995a9b876ba1442/vegolaru.pdf
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/j1emt1lu8dffre90pvlf9t8g5i/piteraxefokinofotelewige.pdf
    • https://atraba-holding.com/userfiles/file/60891050738.pdf
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/0olos398s5iaq2q43rkojmvr4q/defopuzapageribu.pdf
    • http://itkaufmann.com/images/fckimages/file/resinaxulegemo.pdf
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/160742c52837c8---30976147619.pdf
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b494749a30d---sasezizare.pdf
    • https://zweiund40.com/wp-content/plugins/super-forms/uploads/php/files/emg4p4ide7maf5ocrgaem4bd70/6716890937.pdf
    • https://aduanaldelvalle.com/userfiles/file/gixejumenisopid.pdf
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160c949d729ecb---69611034633.pdf
    • http://albino-pitti.com/pub_img/file/59932051495.pdf
    • http://inglewoodreunion.com/clients/68690/File/26157856927.pdf
    • https://www.aserspa.net/wp-content/plugins/super-forms/uploads/php/files/l7qr3928tguqrtbbnp2l8mp9m2/dazedanibujowixeb.pdf
    • http://nedirajtebosnu.net/userfiles/file/xuvufipemaxubikuro.pdf
    • http://jatyn.cn/upfiles/202105/file/1620572086.pdf
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/4aabc9a96e2265c6b92aed0112186901/62538420796.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/8473f080bb4db2960e90be2e832e50cd/16093331560.pdf
    • http://jinanxintiandi.com/userfiles/files/70452046372.pdf
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/b7na6dk92hvspagr5if8gq74q1/58566267899.pdf
    • http://teamwork-poetschke.com/ckfinder/userfiles/files/tiwekemodunaju.pdf
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/15d990165ddc3c2089978ccd40053334/lisuzijibosivepiwipibutu.pdf
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/a3c8d1261f8e25b188226a1a149300dc/vetexitubuk.pdf
    • http://www.redactordecontenidos.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160805489e34e5---tufibixamamedawoxev.pdf
    • http://c2r-auto.com/uploadfiles/file/2021052013261773499.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=meaning+of+number+5+in+hebrew
    • 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_off00011883.bin
a644d7ccc79c8bb548b86799b73eff09bd7d21962e39a10641142f3cf294fa6a
pdf-font-stream PDF embedded font (sfnt) at offset 0x11883 10800 bytes
font_01_sfnt_off00013146.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13146 16792 bytes
font_02_sfnt_off00014958.bin
db6922a169785a2fad147b2361a2a8fd242defcd7c7c80b6e00e1abb128eeb70
pdf-font-stream PDF embedded font (sfnt) at offset 0x14958 17880 bytes