Malicious PDF — malware analysis report

Static analysis result for SHA-256 7fc1cb1d0cdc5aa4…

MALICIOUS

PDF

82.5 KB Created: 2021-06-30 20:09:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 509c2a261ba00dbecbce13aa3bc8f4f1 SHA-1: 81ceb10400665ee5219c1e7be77a65cbd7a6b96f SHA-256: 7fc1cb1d0cdc5aa4f73e11b5120edec1e2afeac9e7d44d200b80af5101eeab43
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to compromised WordPress sites, suggesting it functions as a link farm or phishing lure. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' further supports this, indicating the PDF is used to distribute links to potentially malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://queure.ru/uplcv?utm_term=convert+2.1+kg+to+pounds
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608289aaee983---vigebesox.pdf
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160bc6fd7e43fb---funozukizep.pdf
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/9grljcvj2vhtjb3j7b507f9ch8/gugewebanoxej.pdf
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607b8b564b1d1---pesupojabasajenikasu.pdf
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160c1202b252cd---mugotevakof.pdf
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/blruqrs8fesd26ck5o5p9rcaft/kisolijufimofofemezedulij.pdf
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a6a64708e3---xikomemabufefabi.pdf
    • http://altinay-law.com/images/file/kesatiwagifigobojifus.pdf
    • https://www.helpforbusymums.com/wp-content/plugins/super-forms/uploads/php/files/ea5d2715c75cf7721a8f21a58c6d9528/kegekibi.pdf
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c578e82b091---20061215097.pdf
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/tqfpoovn7i91uct3pc78886ff6/tofoduguxad.pdf
    • https://northstarexecutivesearch.com/wp-content/plugins/super-forms/uploads/php/files/eb4f8cc77bef016f95ee98e612ed1acd/55959167591.pdf
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c90eabab52---kanitinixipexubeb.pdf
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/11b04ed5a8be320d602325471e357fef/nobaliz.pdf
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16099e4923ce18---51479825173.pdf
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/c0707252ea86b4c364e0f5af80abe203/81310353290.pdf
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/f39c2b74993d797003f2bdeda1294b9e/dukokujuvi.pdf
    • http://chunmianxian.com/upfolder/e/files/20210621225314.pdf
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/457586a4vjdn5ep1v989bu95p1/73488618701.pdf
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/b594be04dc8ea07fc569477db9cc5a32/61152349431.pdf
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607e9d15dcc9a---rolopuxarofibinafezubene.pdf
    • http://aryajob.com/user_upload/file/10677702947.pdf
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160af20567c3a7---68171295435.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_off0000e200.bin
26282701dd14fb3647f2a1a095a91f8aae94d0d4e09bb048f471445040ccd493
pdf-font-stream PDF embedded font (sfnt) at offset 0xE200 10796 bytes
font_01_sfnt_off0000fb00.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB00 16792 bytes
font_02_sfnt_off00011312.bin
323633a0be2c276778c86e4beee8a3cd9fb6290e741fca25a6f7be0b38f2f7f5
pdf-font-stream PDF embedded font (sfnt) at offset 0x11312 16168 bytes