Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a527971ffe3e9ef…

MALICIOUS

PDF

87.7 KB Created: 2021-07-24 16:18:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 37c817096076aec618015cf8a25f8607 SHA-1: 85f63a56ee416afb5bde249bbe28f3c4db847afb SHA-256: 4a527971ffe3e9ef60eedfc4631e871811508579af7aea86aaa699a15ed67f3a
156 Risk Score

Malware Insights

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

The file is a PDF identified as malicious by ClamAV and an ML classifier. It contains numerous URLs, many of which point to compromised CMS upload directories, suggesting an attempt to distribute further malicious content or phish users. The presence of 'utm_term' parameters in some URLs indicates a potential phishing or SEO manipulation tactic.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b62ba9b456---xidofedokegusote.pdf
    • http://wurbs-hanau.de/userfiles/file/terenosutozegitamolat.pdf
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160e6f5f4914f9---55228153627.pdf
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/bde4e8dddb7d1601da34f9e00c2d9fe2/47009729052.pdf
    • https://textolinguisticsolutions.com/upload/editor/file/pageduwexifufikatugadok.pdf
    • https://forcechicago.com/wp-content/plugins/super-forms/uploads/php/files/46fd2cdad962691360f2be6d3b79834c/70993771400.pdf
    • http://biancoacolori.it/userfiles/files/tufosinegulowogozawemu.pdf
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/f6e26f90a36b190e0f07863a4219eccd/63158746002.pdf
    • https://learn-atdi.com/uploads/files/vigifirujoweraju.pdf
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a896d475188---86367805202.pdf
    • https://gonguyenkhoi.vn/upload/files/pabamisilapenubenabekexog.pdf
    • http://indexone.ru/upload/file/71470853653.pdf
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096fba3ef1eb---posetarapizoperuzuwagurik.pdf
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a1451940bb8---befugovafosud.pdf
    • https://thehero88vip.com/ckfinder/images_store/files/rabobafunon.pdf
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608ec9d77f8d3---32795549143.pdf
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/014c9d9ce1c2fc6eddc0eda1d582407a/texagawafarala.pdf
    • http://ntweac.edu.hk/admin/ckfinder/userfiles/files/55550544556.pdf
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/2a84b98aea4280488a9f1157d91c8229/madevomijimugofasedujilan.pdf
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c9a07e11627---48751598811.pdf
    • https://majorsagilekvaros.hu/uploads/file/40475126256.pdf
    • http://ufnk.fr/app/webroot/files/file/jezikabowekefovigewuv.pdf
    • http://optykglowacki.pl/obrazki/files/konekeja.pdf
    • https://vidaleve.net/ckfinder/userfiles/files/61601293284.pdf
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16080930ed43d9---lodegader.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=how+much+does+cash+app+charge+to+send+money+to+bank+account
    • 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_off0000f376.bin
f50409be55832edcb3329fb99ec5d4f6e7189875eae12522d5199919b3318faa
pdf-font-stream PDF embedded font (sfnt) at offset 0xF376 16160 bytes
font_01_sfnt_off00011d3f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D3F 16792 bytes
font_02_sfnt_off00013556.bin
853fc037d1ca6f75bb031de62a96eb1e96a7de3c9fe70573277818f496d5c494
pdf-font-stream PDF embedded font (sfnt) at offset 0x13556 11344 bytes