Malicious PDF — malware analysis report

Static analysis result for SHA-256 87075161fab33c6a…

MALICIOUS

PDF

84.9 KB Created: 2021-07-08 07:46:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 68ef802a6f4798f8a38fc1302cb65021 SHA-1: 66993e107d22831c90905c8b9788a24b224ed066 SHA-256: 87075161fab33c6a72bfc179b4f1a69dc179b58521218f2c0b06780ea44982f7
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. The heuristics reveal it functions as a link farm, with many URLs pointing to compromised WordPress upload directories and other potentially untrustworthy domains. The document body is heavily obfuscated and appears to be metadata from the wkhtmltopdf tool, offering no direct user-facing content to analyze for intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://acpiindia.com/userfiles/file/33567352853.pdf In PDF document text
    • https://limmaginebistrot.com/file/saziwuxopadulefinaj.pdfIn PDF document text
    • http://munsusa.org/userfiles/file/20210526114301.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607420de5af58---23968913439.pdfIn PDF document text
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5381a3cc0---3281090362.pdfIn PDF document text
    • https://brs.jo/userfiles/files/gesosog.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/2k1p88m8hbevis0eeoh460bn95/22181746557.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/160836af939893---37343488831.pdfIn PDF document text
    • https://taiwancy.com/app/webroot/userfiles/files/zijenulinitilovab.pdfIn PDF document text
    • http://adveotec.com/img/file/52620856801.pdfIn PDF document text
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b180042546d---kubovat.pdfIn PDF document text
    • https://autotrilogy.com/wp-content/plugins/super-forms/uploads/php/files/d8be37657894ade2ee3077f682efd36e/wizesijunukematutedo.pdfIn PDF document text
    • http://kayapaliinsaat.net/file/sodokivexikatuzux.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/7vc2rbl80j7dmckbffspjdffl5/befibudofakakakaku.pdfIn PDF document text
    • http://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/b064cd9ff6897567279612234ca1f9f4/9063109773.pdfIn PDF document text
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606f312c9172d---84515904991.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080c8d44cec7---jifegebulire.pdfIn PDF document text
    • http://www.aqsclimited.com/EditorImages/file/tivesenoverofadibijepig.pdfIn PDF document text
    • http://opalsolar.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16088914f93531---darowomixebudemurusoso.pdfIn PDF document text
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083c51d87c7c---fitakotuxom.pdfIn PDF document text
    • http://alumcity.ru/userfiles/file/83502029188.pdfIn PDF document text
    • http://accessprecision.com/userfiles/file/sofulobuw.pdfIn PDF document text
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/9e3a81eca2fa12e0ff013bb19f0bf45c/mupumexatuwugifesovoz.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/c76961d63e579ab6a196b62f89793e0c/43011406015.pdfIn PDF document text
    • http://inter-travel.hu/_user/file/wewixokebafetalepejo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=ancient+latin+numbersPDF 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_off0000e8a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8A7 10492 bytes
SHA-256: 2615ab2a1a20afa3aedba058c75305a8311c2874e36ecfc8d402d05cd007e5d9
font_01_sfnt_off0001007e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1007E 17956 bytes
SHA-256: 6e70b535c23fd54253c0afb46d8b0ff100eedcc36be1d7129d666640cbf193f0
font_02_sfnt_off00012e69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E69 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1