Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5bffbdf2e402dbb…

MALICIOUS

PDF

81.2 KB Created: 2021-09-16 18:15:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 25d1d8f2b7e96f677d9705a103bef11a SHA-1: d6234fd43860526969bf3bb35e247ec6628c81b0 SHA-256: f5bffbdf2e402dbb895c96f7c58b617356c605bdfa10da87fecdbca941ceb1cf
116 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains a heuristic indicating it's a callback phishing lure, prompting users to call a phone number for issues like billing or security. While no scripts were extracted, the presence of numerous embedded URLs, some pointing to compromised CMS uploads and link farms, suggests an attempt to host malicious content or redirect users. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 6

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://taperagi.com/contents/files/46639767440.pdf
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140d430901aa---89589334740.pdf
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161356d9022dba---kalesujizidewokikamamu.pdf
    • http://myxroad.net/upload/userfiles/file///vasuwegaxomufidiz.pdf
    • https://nolimitscenter.be/peausitive/images/FCKeditor/file/18723065718.pdf
    • http://sinostandards.net/upload/files/81549550795.pdf
    • http://studioarchterreni.it/userfiles/files/tuxawadulebawekajigadiju.pdf
    • http://montazenabytkupraha.cz/files/file/63331737540.pdf
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/4f90e9c72b9e47d3588113f9f86e0f88/dijidus.pdf
    • http://itps-group.com/uploadfiles/file/wogaxeribefugep.pdf
    • http://vincitydata.com/uploads/ckfinder/files/30111604397.pdf
    • https://ceccarmehedinti.ro/userfiles/file/20063910237.pdf
    • http://studiobaldizzone.com/userfiles/files/kesabefetunok.pdf
    • http://gemaeldeundobjekte.de/uploads/files/77488419866.pdf
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dadd0a9369---sujarejuradi.pdf
    • http://esenkardeslerinsaat.com/resimlerfiles/kizilefuxomimusifiporez.pdf
    • https://e-fasteners.eu/media/file/xunokivugosowesodezube.pdf
    • http://katyababash.com/images/uploads/file/tiget.pdf
    • https://sua.vn/uploads/userfiles/file/kugimakolowozuxix.pdf
    • https://petandpuppies.com/userfiles/file/78309880668.pdf
    • http://xecuoihuyhoang.com/uploads/userfiles/file/nuwofoxogukepuf.pdf
    • https://www.hs-hofgastein.salzburg.at/ckfinder/userfiles/files/xotexaziw.pdf
    • https://toppelletmachine.com/d/files/vodibewifazekenelowot.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=c%2B%2B+it+series+pdf
    • 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_off0000d9ad.bin
3be807fb865e7a1f80b8938c9c751fbca683c3451f211bc577b340aa59d557bc
pdf-font-stream PDF embedded font (sfnt) at offset 0xD9AD 18552 bytes
font_01_sfnt_off00010978.bin
1f8e042c81e2836c914b181df2cfce007af0a2982a2a751815ffeeb19ca16127
pdf-font-stream PDF embedded font (sfnt) at offset 0x10978 10088 bytes
font_02_sfnt_off00012015.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12015 16792 bytes