Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9dc76c980838f8c…

MALICIOUS

PDF

98.9 KB Created: 2021-06-18 05:43:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 6c27d1fcd6f38a7f8d1c1490702522d4 SHA-1: 0f327d667e15b4876302c8115dc60a2f812d24e2 SHA-256: c9dc76c980838f8c5e2882c0c563ca7f1118fe52a98434ef571cd520f4bd0d7d
196 Risk Score

Malware Insights

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

The file was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of an advance-fee scam. It contains numerous links to external PDF files hosted on compromised WordPress sites and disposable domains, suggesting a phishing or scam campaign. The document body, though heavily obfuscated, contains metadata related to 'amsco ap human geography 2020 answer key' and the authoring application 'wkhtmltopdf', which appear to be decoys.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Advance-fee lottery/parcel scam lure high SE_ADVANCE_FEE_SCAM_LURE
    Document contains lottery/beneficiary or prize language together with large-value draft/funds wording and parcel/courier delivery requirements. This is a classic advance-fee fraud document shape.
  • 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://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2b567c9adc---fupuvefefi.pdf
    • https://bettyloupaints.com/userfiles/files/76132338071.pdf
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e989eddf18---sixirujonotukafironomaluf.pdf
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080f740385e5---34096759239.pdf
    • http://baaningdoi.com/file_media/file_image/file/55872005344.pdf
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/97eb8a72e354b7d73579d047a31987d3/89223056731.pdf
    • http://progfin.pl/userfiles/file/34643359281.pdf
    • https://alternatifhirdavat.com/upload/ckfinder/files/42053143339.pdf
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/70d2e858bbe37023020f26646eb5dd56/15230117852.pdf
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084e98c25653---7722410017.pdf
    • http://nanumed.ro/uploads/files/68133526923.pdf
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086332ab5e6e---36816770233.pdf
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/5dme2l9r09smt9gl0bs818t0f6/jikadawezixu.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f33309e8d1---xirefotad.pdf
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b65a46a8614---94912435848.pdf
    • http://nmglyxx.com/userfiles/file/bokoriwenozuke.pdf
    • http://eibich.de/layout/bilder/file/veturomudasajabarowoko.pdf
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/db6589965f8d9aa82b1c4b2a76ca39ab/gokomoziwoza.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=amsco+ap+human+geography+2020+answer+key
    • 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://scripts.sil.org/OFL
    • 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_off0001290d.bin
799c63cbf1d5633f5ae4f3c197bef0b3a60524f2d1b12c767cef4f666eaf4b65
pdf-font-stream PDF embedded font (sfnt) at offset 0x1290D 5836 bytes
font_01_sfnt_off00013cdb.bin
7562597821387248ba5362b577f6136e13efbfa2a2e37301eea569c2000806ee
pdf-font-stream PDF embedded font (sfnt) at offset 0x13CDB 12284 bytes
font_02_sfnt_off000166a9.bin
d0e7b9ba29d057aa6ae202cf3951f64b785722680a0e11a35ff30fc306d51026
pdf-font-stream PDF embedded font (sfnt) at offset 0x166A9 16260 bytes