Malicious PDF — malware analysis report

Static analysis result for SHA-256 84534c9922e52adb…

MALICIOUS

PDF

83.5 KB Created: 2021-07-14 00:16:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b4abe0ae69181140edcb92f67ccc349c SHA-1: 8573ca62d427fa4cd0b6c2ab7d0c2cfb1e2f3be1 SHA-256: 84534c9922e52adb9a1a5e0f88c24427d9a5c8ed739582cace22f631d7651442
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous PDFs hosted on compromised WordPress sites, indicating a likely attempt to distribute further malicious content. The ML classifier strongly flagged this PDF as malicious, and heuristics identified it as a link farm on disposable hosting, suggesting a campaign to redirect users to malicious payloads. No scripts were extracted, but the structure and URL patterns are indicative of a downloader or redirector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • 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://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/160b834714da82---57068385630.pdf
    • http://cjandjunemillerfarm.com/clients/75830/File/26945509478.pdf
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607c2257c9423---kagukugu.pdf
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160ac797809b6e---39492417109.pdf
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160abfd7b4e989---21107584353.pdf
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/705ee6a4094b46e2156e591a30cad5a8/3347433678.pdf
    • http://nyett.hk/uploads/news/files/68714738453.pdf
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/2a90685247fc5d6e9b75aeb0b9e4deb5/leruvetokogef.pdf
    • https://vinisfarm.com/wp-content/plugins/super-forms/uploads/php/files/57f5d843fba96f329f53a99299e5d4c1/sejiwojujo.pdf
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d0ecb807ba---45677145374.pdf
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607ae935b74c2---vivudomugipok.pdf
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160713aacebe70---muforovasene.pdf
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099e520cf85e---48462545473.pdf
    • https://nikosdimos.gr/userfiles/file/54960482506.pdf
    • http://e-sportis.com/images/upload/15746405183.pdf
    • https://puntoagricoltura.it/file/11016028248.pdf
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d42d8c805e---40161849872.pdf
    • http://pc-driver.ru/userfiles/files/3219197516.pdf
    • http://lyzjkgm.com/d/files/75890564438.pdf
    • http://thecreditcrisis.net/clients/73966/File/89668144681.pdf
    • http://jagatjyotischool.org/jagatjyotischool/userfiles/file/nufupew.pdf
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a75f69a3b0b---55352078573.pdf
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b83adc67a14---19566451436.pdf
    • https://stopserv.ru/files/file/66244977056.pdf
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/t2vd0ne41uqigj6538ok1670o4/fatibaxigupuluwosane.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=sun+and+moon+warm+and+cool+colors
    • 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_off0000e4e0.bin
ef957cd045c33d940e0598f9aab2577dc76bbd59ee3672373455a20b9854f923
pdf-font-stream PDF embedded font (sfnt) at offset 0xE4E0 16744 bytes
font_01_sfnt_off000110a3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x110A3 16792 bytes
font_02_sfnt_off000128ba.bin
84149703f0c1eb10144f3572aab80164928cab0c9f7f107a3839dbe5d231ddeb
pdf-font-stream PDF embedded font (sfnt) at offset 0x128BA 10472 bytes