Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6d8c2bbc4ad7a89…

MALICIOUS

PDF

73.9 KB Created: 2021-09-07 05:18:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 42428b5396f0d7c7d21e03319ed6e4d9 SHA-1: 822c80dba656a273a7576fdff39af459e511e129 SHA-256: a6d8c2bbc4ad7a89fe1e0df1549f91d2f1018fa533a61fe86c0be9c0fbc88dc8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Numerous heuristics point to the PDF acting as a link farm, directing users to compromised WordPress sites and other suspicious domains, likely for phishing or malware distribution. The presence of external URIs and link farms suggests an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://irlanc.ru/uplcv?utm_term=zkteco+k20+pdf PDF link annotation
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607e24af34c23---74687077245.pdfIn PDF document text
    • http://amctop.com/board_data/editor_img/file/202106012155.pdfIn PDF document text
    • http://selfmadefilms.nl/userfiles/files/57947956887.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609458c2ccc15---jaragabos.pdfIn PDF document text
    • http://bellina.pl/userfiles/file/xufovunuwavavuxorezalexu.pdfIn PDF document text
    • http://preserveproperties.com/userfiles/files/69056999192.pdfIn PDF document text
    • http://stinpo.com/ckfinder/userfiles/files/24759211815.pdfIn PDF document text
    • http://maplewoodmachine.com/clients/1/17/17f0ea2532424b9b8bf99baf53cd3763/File/75552622871.pdfIn PDF document text
    • http://busankid.com/webfiles/board/file///mosakodolawitusun.pdfIn PDF document text
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16105edf5d6a08---rijabimavuwisadipipa.pdfIn PDF document text
    • http://brezov-gaj.si/uporabnik/file/xugakoweb.pdfIn PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609260af9a138---kisivolejekufeti.pdfIn PDF document text
    • http://kpdb.org/userfiles/files/xivufemivuva.pdfIn PDF document text
    • http://rungrawin-itt.com/userfiles/files/juvepalule.pdfIn PDF document text
    • https://e-lightingcontrols.com/wp-content/plugins/super-forms/uploads/php/files/6bf78fd15062f2f5224bf0cbe895fe29/38655690046.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1606ded4dd3239---ledejajito.pdfIn PDF document text
    • http://vietdubai.com/userfiles/file/64414906305.pdfIn PDF document text
    • https://brianspradlin.com/userfiles/file/62140850032.pdfIn PDF document text
    • http://www.eau-msu.ru/ckfinder/userfiles/files/36129258282.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/16107fa244b562---47754053101.pdfIn PDF document text
    • http://alliance-vietnam.com/upload/files/bokogevurapixafalibivevo.pdfIn PDF document text
    • http://coffee33.ru/archive/file/80592264560.pdfIn PDF document text
    • http://www.tecnobor.com/ckfinder/userfiles/files/ziwadotipitagobotizafenos.pdfIn PDF document text
    • https://cald-lighting.com/wp-content/plugins/super-forms/uploads/php/files/4dcbef7fb8a2c53da3086eee270b6065/dogovisalobejujuxafik.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/b7gaaal4ske4qov7ibl0s73ri3/8641950125.pdfIn PDF document text
    • 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_off0000bb39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB39 18240 bytes
SHA-256: d2128c966948c4ea0681e0b278fb368e87e7fdd8a1ac606c5bc99ac6525043dd
font_01_sfnt_off0000eb20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB20 10236 bytes
SHA-256: 792154a71c6728db9a334a837c7244f86aec588ab2fcbcb277c14821216c56f3
font_02_sfnt_off0001025a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1025A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1