Malicious PDF — malware analysis report

Static analysis result for SHA-256 173564b711b3f640…

MALICIOUS

PDF

80.1 KB Created: 2021-06-27 20:36:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8c586116afa249fdda9576c99c0a0995 SHA-1: 9b4904a132ae9f910f264aad37868a8f2444dc9a SHA-256: 173564b711b3f640bf85d3ee8ebc5d5243d6ec115341a65076089c8bf500b295
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document contains a link farm pointing to multiple websites, many of which are hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable binary data, suggesting it's not intended for human consumption but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 https://www.spreefahrten-berlin.de/wp-content/plugins/super-forms/uploads/php/files/bks2qn8iq66eq4pdsq57ssoffj/40064358126.pdf
    • https://rinducm1.com/contents//files/zezokisidulikefupab.pdf
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a881f28eeb1---gimit.pdf
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084b3b531bf0---37774787990.pdf
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/e209e11cd1aa9a6bd430543f289ccea1/85222888455.pdf
    • http://nextgt.eu/uploads/file/kirirotupojigujubu.pdf
    • http://thuephotocopytaihanoi.com/upload/files/ruruxusenutitawi.pdf
    • https://eyetracking.pl/userfiles/file/xigetuduzokujajelito.pdf
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608106f74438c---jisojuvuzetusadixadodeke.pdf
    • https://stehovani-ostrava.cz/static_pages_files/file/94721248255.pdf
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/1606c82f5a759a---gekegexusuvajuw.pdf
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/2p8rgsj996of6cuq0n0a01dsdj/wemovulinaxubozadu.pdf
    • http://dynamic1984.com/user_file/file/zuzoputolivofulej.pdf
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b7a9d8da03---fexazepazodul.pdf
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c8645b8cbf---jetofetevifiwamejakig.pdf
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ded1ddd106---gelomejasosukizij.pdf
    • http://amandamaitland.com/images/file/42892947451.pdf
    • https://wecafephuket.com/wp-content/plugins/super-forms/uploads/php/files/qni1kc24sqgo3rjdttpp21eqlr/82664212988.pdf
    • http://bamt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160abe709b7738---29551324894.pdf
    • https://bisnismedsos.com/userfiles/file/7938783066.pdf
    • http://drjoecarver.com/clients/49355/File/86015788162.pdf
    • http://ptairsupply.com/userfiles/file/rubunakeweve.pdf
    • http://richmore.kr/uploadfile/fckeditor/file/wajitotizapokiwazed.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=i+will+always+love+you+piano+sheet
    • 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_off0000d386.bin
307876c23ae4394183b6dd97baca566f14dc6044347175b08c617c550353daf6
pdf-font-stream PDF embedded font (sfnt) at offset 0xD386 18752 bytes
font_01_sfnt_off0001032d.bin
1525e7b34bd30f57b77c107876c7037a5becbd271ab303a981c204518d5289a2
pdf-font-stream PDF embedded font (sfnt) at offset 0x1032D 10564 bytes
font_02_sfnt_off00011b49.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B49 16792 bytes