Malicious PDF — malware analysis report

Static analysis result for SHA-256 557470e4ecfe73a8…

MALICIOUS

PDF

91.5 KB Created: 2021-07-18 01:57:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c859984416d8659099f3c03dac0571a6 SHA-1: de710f14cea914a0b1867c6c4d02e50d6bb66c1b SHA-256: 557470e4ecfe73a881edd0fcc72dd7f137a7341c0cb8c050ca6a93718ed088f7
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 high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with numerous URLs pointing to compromised CMS uploads and disposable hosting. These links are likely used to distribute phishing content or further malware stages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://gemculture.com/userfiles/file/90691460169.pdf
    • https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/eccb7be1f1bc092420af5df2a75ba762/59050970918.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607ae17e8f473---xabobapugiso.pdf
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f3f6b0b886---gabulopexenafifal.pdf
    • https://istanajp2.com/contents//files/42121964031.pdf
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608990e815100---27574266688.pdf
    • http://xn--9p4b29dncp2cc6y.net/upload/fckeditor/file/kusebedikekofogigo.pdf
    • http://nsk-nalogov.net/upload/files/64138160932.pdf
    • http://xn--80aafbkbafwdti1ahihccrg.xn--p1ai/pict/file/79317674514.pdf
    • https://sitpchemcieszyn.pl/_sitpchem/file/tobikumek.pdf
    • http://sansboundaries.com/clients/f/fd/fde0d4b6b324343791c5f0705b221951/File/32556391883.pdf
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b00ed8ac237---36575114557.pdf
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d17c2b2e09---53421405156.pdf
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/d8luc2r8mpn4fgi2dmfoekj97u/zuxizubemukinulegozo.pdf
    • https://drmarlenebothma.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16083582514b5f---mexuteseritewoxu.pdf
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/973ede603a199acd15c70216b9d67dcb/95070665890.pdf
    • http://wintec-samu.hu/uploads/files/2083398274.pdf
    • http://mobilesamara.com/img/files/file/getudigadofawiv.pdf
    • http://zjxfjc.com/uploadfiles/files/80035149645.pdf
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16080cf464646e---vazusofebo.pdf
    • http://www.urbanwaterways.info/files/pavurarosurobiko.pdf
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/4eb7385ba184afa75f6d7250db42ef71/viburenogazujonimujilu.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=species+richness+and+evenness
    • 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_off0000ffea.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFEA 16792 bytes
font_01_sfnt_off000117fc.bin
43369ff074811cbce7f18dc746fd415ceb1872658551d11546a7379da11d20f8
pdf-font-stream PDF embedded font (sfnt) at offset 0x117FC 17980 bytes
font_02_sfnt_off000147ab.bin
43d4647a72a2ba95b8c61a2ccaee3706f00db7b57d53fb7b96666059822b3cec
pdf-font-stream PDF embedded font (sfnt) at offset 0x147AB 10488 bytes